Polymer, process and composition

ABSTRACT

There are described q oligomer-polymer composition [optionally substantially free of styrene (&lt;1.5 wt-% of copolymer)] comprising oligomer composition O having a weight average molecular weight of from 1000 to 150,000 g/mol (measured by GPC) and polymer composition P having a weight average molecular weight of at least 80,000 g/mol (measured by GPC) the oligomer composition O and the polymer composition P each independently comprising a copolymer composition comprising: (a) at least 8.5 wt-% preferably &gt;=20 wt-% of a higher itaconate diester (preferably dibutyl itaconate—DBI); (b) less than 23 wt-% acid monomer but also sufficient to have an acid value less than 150 mg KOH/g of polymer, (c) optionally with less than 50 wt-% of other itaconate monomers, and (d) optionally less than 77 wt-% of other monomers not (a) to (c). The DBI may be biorenewable. One embodiment is an aqueous dispersion of vinyl sequential polymer of two phases: A) 40 to 90 wt-% of a vinyl polymer A with Tg from −50 to 30° C.; and B) 10 to 60 wt-% of a vinyl polymer B with Tg from 50 to 130° C.; where DBI is used to prepare A and/or B and polymer A has from 0.1 to 10 wt-% of at least one acid-functional olefinically unsaturated monomer. Another embodiment is an aqueous polymer coating composition of a vinyl oligomer C of Mw from 1,000 to 150,000 g/mol and an acid value&gt;5 mgKOH/g; and a vinyl polymer D of Mw&gt;=80,000 g/mol and an acid value&lt;10 mgKOH/g where D is obtained from DBI and the amount of monomers used to form C and D fall into the respective weight ratios 5 to 70 for polymer C and 95 to 30 for polymer D. A further embodiment is an aqueous suspension polymerization process for preparing vinyl polymer beads from olefinically unsaturated monomers and a free-radical initiator, where at least 10 wt-% of the monomer is DBI.

This application is the U.S. national phase of International ApplicationNo. PCT/EP2013/052172 filed 4 Feb. 2013 which designated the U.S. andclaims priority to EP 12153842.5 filed 3 Feb. 2012; EP 12153840.9 filed3 Feb. 2012; EP 12153839.1 filed 3 Feb. 2012; EP 12153838.3 filed 3 Feb.2012; EP 12175782.7 filed 10 Jul. 2012; EP 12175784.3 filed 10 Jul.2012; EP 12175785.0 filed 10 Jul. 2012; EP 12175786.8 filed 10 Jul.2012; EP 12175788.4 filed 10 Jul. 2012, the entire contents of each ofwhich are hereby incorporated by reference.

The present invention relates to polymers and polymeric materialsobtained and/or obtainable from certain 2-methylidenebutanedioatediester monomers (also referred to herein as higher itaconate diesters)to a process for making such a polymers and their use to prepare forexample coatings, inks and/or adhesives. It is preferred that polymersof the invention, and/or the higher itaconate diesters, are obtainedfrom bio-renewable sources.

Many conventional polymers often suffer from undue sensitivity to water.This is especially true for water based polymer emulsions which cansuffer from an increased water sensitivity compared to their solventborne counterparts. A common way of countering this is to incorporatevery hydrophobic monomers, such as butyl acrylate (BA) or 2-ethylhexylacrylate (EHA). However, as homopolymers from these monomers have anextremely low Tg, incorporation of large amounts of these monomersproduces a composition which is very often too soft (low Tg), yet is notsufficient hydrophobic if the amount of these monomer is sufficientlylow to produce a satisfactory Tg. This might in turn be mitigated byintroduction of high Tg, hydrophobic monomer such as styrene and thelike. However polymer compositions comprising stryenic monomers, sufferfrom reduced outdoor durability because of the inherent UV sensitivityof styrene.

We have now surprisingly found that the dilemma described above can besolved. Good water resistance and low water sensitivity combined withhigh hardness and high elongation at break may be achieved byintroducing higher ester itaconates such as dibutyl itaconate (DBI) asthe hydrophobic monomer. Even though these monomers are veryhydrophobic, the applicant has unexpectedly found that polymers madefrom higher itaconate esters do not suffer the same reduction inhardness typically observed for copolymers made from high concentrationsof the typical hydrophobic monomers such as butyl acryate (BA) and/or2-ethyl hexyl acrylate (EHA).

Itaconate ester monomers have been described for very many years.However they have not been widely used to make commercial vinyl polymersbecause they are expensive and difficult to process. Prior art documentsdescribe the use of itaconate esters only in general terms and typicallydescribe or exemplify lower itaconate diesters such as dimethylitaconate (DMI). The few documents which describe higher itaconateesters are described below.

U.S. Pat. No. 4,206,292 (Kureha Kagaku Kogyo Kabushiki Kaisha) describesa vinyl chloride resin coating with a smooth surface. The coatingcomprises: (1) 100 parts of vinyl chloride polymer; and (2) 0.1 to 30parts of a polymer processing aid comprising: (A) 10 to 100 parts of acopolymer comprising 20 to 99% of an alkyl methacrylate, 1 to 70% of adialkyl itaconate, and 0 to 60% of a copolymerizable monomer; and (B) 0to 90 parts of a copolymer comprising 80 to 100% of an alkylmethacrylate, and 0 to 20% of a copolymerizable monomer. The vinylchloride resins are not prepared from bio-based or other environmentallybenign sources. The maximum amount of DBI that is used in the examplesis 30% by weight.

U.S. Pat. No. 4,547,428 (Monsanto) describes a terpolymer comprisingrepeating units derived from an olefin, a diester of an additionpolymerizable unsaturated dicarboxylic acid, and a solubilizing monomerwhich promotes compatibility between the terpolymer and a vinyl halidepolymer. A granular form of the processing aid and a method for itspreparation are also disclosed. These polymers are not suitable forcoating applications and the highest concentration of DBI in theexamples is 17% by weight.

U.S. Pat. No. 4,588,776 (Monsanto) describes a polymer compositioncomprising a blend of a vinyl halide polymer and a particulateterpolymer having a molecular weight of at least 100,000 and a glasstransition temperature of at least 50° C. The terpolymer comprisesrepeating units derived from an olefin, a diester of an additionpolymerizable unsaturated dicarboxylic acid, and a solubilizing monomerwhich promotes compatibility of the terpolymer with the vinyl halidepolymer. These polymers are used to prepare shaped plastic articles andnot for coating applications. The maximum concentration of DBI used inthe examples is 17% by weight.

U.S. Pat. No. 6,951,909 (3M) describes a polymerizable system comprisesan organoborane, at least one polymerizable monomer, and a work-lifeextending agent. These compositions are not suitable for coatingapplications and the maximum concentration of DBI used in the examplesis 17% by weight.

WO11/073,417 (DSM) discloses an aqueous emulsion comprising at least avinyl polymer, said vinyl polymer comprising: a) 45 to 99 wt-% ofitaconate ester monomers having formula (I), wherein R and R′ areindependently an alkyl or an aryl group; b) 0.1 to 15 wt-% of ionic orpotentially ionic unsaturated monomers; c) 0 to 54 wt-% of unsaturatedmonomers, different from a) and b); and 0.9 to 54.9 wt-% by weight oftotal monomers of a chaser monomer composition added subsequently andpolymerised after the polymerisation of monomers a), b) and c); whereina)+b)+c) and the chaser monomer composition add up to 100 wt-%; andwherein the aqueous emulsion contains less than 0.5 wt-% free itaconateester monomers of formula I based on the total weight of the aqueousemulsion. Although it is a stated object of the invention to provide avinyl polymer with a high total concentration of itaconate estermonomers (see page 2, lines 14 to 17) in practise the larger proportionof such itaconate esters are lower itaconate esters (i.e. esters ofsmall alkyl groups such as DMI). This document does not teach that itwould be desirable to use a high concentration of higher itaconateesters (i.e. esters of large alkyl groups such as DBI). Indeed '417states that itaonate esters are difficult to process (see page 2, lines23 to 25) which combined with the teaching of the examples demotivates areader to incorporated large amounts of hydrophobic higher itaconateesters like DBI in a copolymer.

The only examples in '417 that describe use of a DBI monomer areExamples 2, 4, 5 and 6. The amounts of DBI and other monomers used toprepare these Examples is given in Table A below. It can be seen thatDBI is used as comonomer only at a low concentrations in the finalcopolymer prepared in these Examples (at a maximum of 22.7 wt-%) whichare each also prepared with significant amounts of another hydrophobicmonomer butyl acrylate (BA). A styrene chaser monomer is always presentin the final product (at least 1.5 wt-%). These examples teach away fromusing DBI or other higher itaconate esters to replace common hydrophobicmonomers such as BA, EHA and/or styrene. No significant improvement isseen in film properties such as hardness and water sensitivity of thecopolymers prepared in this document.

GB1009486 (Borden) describes a latex of composite polymeric particleswhere the core and shell may comprise a copolymer of a vinylidenechloride and an ester of an alpha unsaturated aliphatic acid (the amountof ester in the shell being greater than the core). One example (Example3) describes use of dibutyl itaconate (DBI) as the ester in an totalamount of 17% by weight of total monomers (5% in the outer shell and 12%in an inner non core layer). These composite multi-layer polymerparticles address a problem of providing a water vapour barrier coatingfor paper and the like and they use much lower amounts of DBI than thepresent invention.

TABLE A (prior art DBI examples from WO11/073417) Monomers/wt-% (1 d.p.)Example Plex S Total of ′417 Composition AA BA MMA 652 DAAM MAA DMI DBI(chaser) Itaconate Ex 2 Initial feed 2.0 28.0 — — — — 45.0 25.0 — 60.0Single phase 1.8 25.2 — — — — 40.5 22.5 10.0  63.0 copolymer Ex 4 Firstfeed 4.4 32.4 13.2 — — — 20.0 30.0 — 50.0 Second feed 5.0 11.0 34.0 — —— 45.0 5.0 — 50.0 Sequential copolymer 4.1 25.5 15.8 — — — 22.7 22.7 9.145.4 Ex 5 First feed 4.2 30.0  9.5 8.4 — — 19.1 28.7 — 47.8 Second feed4.7  9.3 28.8 9.5 — — 42.9 4.7 — 47.6 Sequential copolymer 3.9 23.6 12.27.9 — — 21.8 21.8 8.7 43.6 Ex 6 Olg initial feed 35.4 — — — 8.0 5.0 51.6— — 51.6 Olg-plr initial feed — 41.2 — — — — 17.6 41.2 — 58.8 Polymer -oligomer 26.8 10.7 (inc 2.2 BA — — 6.1 3.8 42.7 8.5 1.5 51.2 chaser) InExamples 2, 4 and 5 of WO11/073417-the chaser monomer was 100 wt-%styrene, in Example 6 the chaser monomer composition was a mixture ofstyrene (40 wt-%) and BA (60 wt %).

U.S. Pat. No. 3,766,112 describes a high gloss latex for floor polishcomprising a chlorinated paraffin wax with a polyvinyl pyrrolidoneprotective colloid. Four monomer components used to prepare the colloid:styrene (70 to 85%), 2-ethylhexyl acrylate (EHA) (5 to 15%)(meth)acrylic acid (3 to 10%) and a fourth monomer (1 to 5%) allpercentages by weight of total monomers of the polyvinyl pyrrolidone.One of the seven monomers suggested as the fourth monomer is DBI. Thesepolymers address the problem of providing high gloss floor coatings andDBI is used in much lower amounts than in the present invention.

US2011-144265 (Durant Yvon) describes polymer particles prepared bypolymerising esters of itaconic acid in the presence of seed particlesto control particle size.

WO2002-068479 (3M) describes polymerisation of (meth)acrylic monomersusing a two part initator system of organoborane amine complex and anactivator. One of the many different examples (Example 6) is preparedfrom a low amount of DBI (20% by weight) and this example does not useany other itaconate diester monomer.

WO 2007-026949 (Nippon Cat.) describes emulsion resin compositions thathave a minimum film forming temperature (MFT) of ≦0° C. and are free ofvolatile organic compounds (VOC). These compositions are obtained bymixing a polymer with a high glass transition temperature (high Tg) witha polymer with low Tg. These polymers may be water dispersible and awide variety of carboxy acid fucnctional acid monomers are suggested toimpart such water solubility including itaconic acid, mono-methylitaconate ester and mono butyl itaconate ester (see page 12 lines 12 to14). No other itaconic acid derived monomers are described and a readerof this document would have no reason to incorporate (non carboxy-acidfunctional) itaconate diester monomers.

The esters (including both mono and di-esters) of2-methylidenebutanedioate (also referred to herein generically asitaconate esters) may be represented by Formula A:

where Ra and Rb can independently be H or any optionally substitutedhydrocarbo moiety (such as any aliphatic, cycloaliphatic or aromaticmoieties) provided that Ra and Rb are other than H (which is not anester but itaconic acid).

It has been found that certain hydrophobic itaconate diesters (e.g. diesters of large alkyl groups) are difficult to use in conventionalpolymerisation processes (especially in aqueous emulsion polymerisation)and are also expensive. Therefore there has been a reluctance to usesuch hydrophobic higher itaconate esters at high concentrations in suchprocesses.

It is an object of the present invention to solve some or all of theproblems identified herein for example by providing polymeric materialsmade from larger amounts of higher itaconate esters (such as DBI)optionally together with other olefinically unsaturated monomers (alsooptionally from a biorenewable source). The resultant polymers may havevarious additional advantages as well as those already described hereinsuch as good film forming at room temperature with the films having highflexibility (elasticity) and good resistance to blocking.

Therefore broadly in accordance with the present invention there isprovided a oligomer-polymer composition [optionally substantially freeof styrene (<1.5 wt-% of copolymer)] comprising oligomer composition Ohaving a weight average molecular weight of from 1000 to 150,000 g/mol(measured by GPC) and polymer composition P having a weight averagemolecular weight of at least 80,000 g/mol (measured by GPC) the oligomercomposition O and the polymer composition P each independentlycomprising a copolymer composition comprising (preferably consistingessentially of):

-   -   (a) greater than 8.5 wt-%, usefully >15 wt-%, preferably at        least 20 wt-%, more preferably at least 24 wt-%, more preferably        at least 30 wt-% for example at least 45 wt-% of at least one        monomer represented by Formula 1

-   -    where both R₁ and R₂ independently represent an optionally        substituted hydrocarbo moiety having from 4 to 10 carbon atoms.    -   (b) optionally at least one hydrophilic monomer preferably in an        amount less than 23 wt-%, more preferably 0.5 to 15 wt-%, and        also in an amount sufficient that the resultant polymer has an        acid value of from 0 to 150 mg KOH/g, preferably less than 150        mg KOH/g, more preferably from 3 to 100 mg KOH per g of polymer,    -   (c) optionally less than 50 wt-%, for example from 0.01 to 10        wt-% and/or one or more monomers represented by Formula 2

-   -    (Formula 2 including itaconate diester monomers being other        than those represented by Formula 1)    -    where R₃ and R₄ independently represent H or an optionally        substituted hydrocarbo moiety having from 1 to 20 carbon atoms    -    X₁ and X₂ independently represents O or NR₅ where R₅ denotes H        or an optionally substituted hydrocarbo moiety having from 1 to        20 carbon atoms with the proviso that when X₁ and/or X₂ are O        then the respective R₃ and/or R₄ attached to the oxy group        independently represent an optionally substituted hydrocarbo        having from 1 to 3 carbon atoms    -   (d) optionally less than 80 wt-%, usefully less than 77 wt-%,        preferably less than 75 wt-%, more preferably <70 wt-%, most        preferably <65% wt-% of monomers other than components (a), (b)        or (c).    -   where the weight percentages (also denoted herein as “% by        weight” and/or “wt-%”) of amounts of (a), (b) (c) (d) are        calculated as a proportion of the total (weight) amount of        (a)+(b)+(c)+(d) which thus totals 100%.    -   where at least one component (a) is present in either oligomer        composition O or polymer composition P.    -   Oligomer—polymers and/or copolymers of or in the invention may        also be limited by one or more of the following optional        provisos:    -   (I) when component (a) consists of DBI in an amount of less than        30% by weight of the total monomers then the copolymer is        substantially free of any chloro groups; and    -   (II) when component (a) consists of DBI in an amount of less        than 23%, preferably from 8.5 to 15% by weight of the total        monomers then the copolymer is prepared by other than an        emulsion polymerisation method in which a chaser monomer is        used;    -   (III) when component (a) consists of DBI in an amount of less        than 23% by weight of the total monomers then if component (d)        is present, component (d) is other than styrene or a mixture        consisting of butyl acrylate (60 wt-% of mixture) and styrene        (40 wt-% of mixture)    -   (IV) the copolymer is substantially free of styrene (preferably        styrene free), more preferably component (d) if present is other        than styrene or a mixture consisting of butyl acrylate (60 wt-%        of mixture) and styrene (40 wt-% of mixture), more preferably        component (d) if present is other than styrene (S), butyl        acrylate (BA), 2-ethyl hexyl; acrylate (EHA) or mixtures        thereof.    -   (V) is prepared by other than an emulsion polymerisation method        in which a chaser monomer is used; and    -   (VI) the copolymer is prepared by other than an emulsion        polymerisation method in which a chaser monomer is used        optionally this proviso applying only when component (a)        consists of DBI preferably in an amount of from 8.5 to 15% by        weight of the total monomers (a)+(b)+(c)+(d).    -   (VII) when component (a) consists of DBI then component (a) is        present in an amount other than 8.5 wt-%, 21.8 wt-%, 22.5 wt-%        or 22.7 wt % of the total monomer composition, preferably other        than from 8 wt-% to 23 wt %,    -   (VIII) when component (a) consists of DBI then component (a) is        present in an amount other than 4.7 wt-%, 5.0 wt-%, 8.5 wt-%,        21.8 wt-%, 22.5 wt-%, 22.7 wt %, 25.0 wt-%, 28.7 wt-%, 30.0 wt-%        or 41.2 wt-% of the total monomer composition, preferably other        than from 4 wt-% to 42 wt %,    -   (IX) the copolymer is obtained other than from a polymerisation        of a dimethyl itaconate (DMI) and dibutyl itaconate (DBI) in the        respective weight ratio of 15 to 85 in the presence of poly        diethyl itaconate seed polymer; more preferably the copolymer is        obtained other than from polymerisation of dialkyl itaconate(s)        in the presence of a poly diethyl itaconate seed polymer; most        preferably the copolymer is obtained other than from        polymerisation in the presence of a poly dialkyl itaconate seed        polymer;    -   (X) if polymerisation of the copolymer occurs in the presence of        an initiator system comprising organoborane amine complex and an        activator then component (a) is present in an amount greater        than 20 wt-%, preferably at least 24 wt-% of total monomers        (a)+(b)+(c)+(d).

As used herein the term seed polymer is as defined in US2011-144265(e.g. see paragraph [007]) i.e. a polymer seed particle is dispersed inan aqueous medium such that the seed particle absorbs further added(co)monomer and the seed particle is present at a concentration to allowfor control of particle size of that (co)monomer.

Preferably the copolymer composition is an emulsion copolymer (usefullyan emulsion polymer prepared where no chaser monomer has been used),more preferably an aqueous emulsion copolymer, most preferably anaqueous coating composition.

Conveniently the composition is substantially free of polyvinyl chloridepolymer and/or chlorinated paraffin wax, more preferably issubstantially free of any monomer comprising chloro groups, mostpreferably is substantially free of any species comprising Cl whether asa substituent, atom, di-molecule, ion or otherwise

Broadly there is provided in a yet further aspect of the presentinvention a process for preparing a copolymer comprising the step ofpolymerising polymer precursors in a polymerisation method the polymerprecursors comprising component (a), component (b) and optionallycomponent (c) and/or component (d) as described above.

to obtain a copolymer.

Preferably the polymerisation method is selected from an emulsion and/orsuspension polymerisation.

Another aspect of the invention broadly provides for a copolymerobtained and/or obtainable by a process of the present invention.

Hydrophobic Component (a) (Higher Itaconate Esters)

The present invention is particularly concerned with polymers obtainedand/or obtainable from a narrow class of itaconate diester monomersselected from the broad disclosure of general itaconate esters ofFormula A. Thus the hydrophobic component (a) comprises itaconatediester(s) of Formula 1:

where both R₁ and R₂ independently represent an optionally substitutedhydrocarbo moiety having from 4 to 10, preferably from 4 to 8, morepreferably from 4 to 6, most preferably 4 carbon atoms.

The diesters of Formula 1 are also referred to herein as higheritaconate diesters.

Usefully R₁ and R₂ may independently represent optionally substitutedC₄₋₁₀alkyl and/or C₄₋₁₀aryl, more usefully C₄₋₈alkyl and/or C₄₋₈aryl andmost usefully C₄₋₆alkyl, even more usefully butyl (n-butyl beingespecially useful).

Whilst R₁ and R₂ may be different, more conveniently they representidentical moieties. Especially preferred examples of Formula 1 includethose where R₁ and R₂ are identical, such di(benzyl)itaconate,di(phenyl)itaconate, di-n-butyl itaconate, di-i-butyl itaconate, and/ordi-2-ethyl hexyl itaconate. Where R₁ and R₂ both represent n-butylFormula 1 represents dibutyl 2-methylidenebutanedioate (also referred toherein as di(n-butyl)itaconate or DBI) which has the followingstructure:

DBI is the most preferred monomer for use as component (a) in thepresent invention.

The itaconate functional component (a) is present in the compositionsand/or copolymers of the invention in an amount of greater than 8.5%wt-%, usefully 15 wt-%, preferably at least 20 wt-%, usefully at least24 wt-%, more usefully at least 30 wt-%, even more usefully at least 35wt-% and most usefully at least 40 wt-%, for example at least 50% basedon the total weight of monomers (a), (b), (c) and (d) used to preparethe copolymer being 100%.

Conveniently the itaconate functional component (a) may be present inthe compositions and/or copolymers of the invention in an amount of lessthan 80 wt-%, more conveniently less than 70 wt-%, even moreconveniently less than 65 wt-%, most conveniently less than 58 wt-%, andfor example less than 55 wt-%; based on the total weight of monomers(a), (b), (c) and (d) used to prepare the copolymer being 100%.

Preferably the itaconate functional component (a) may be present in thecompositions and/or copolymers of the invention in an amount of from 20to 80 wt-%, more preferably from 24 to 70 wt-%, even more preferablyfrom 30 to 65 wt-%, most preferably from 35 to 65 wt-%, for example from40 to 55 wt-% based on the total weight of monomers (a), (b), (c) and(d) used to prepare the copolymer being 100%.

Hydrophilic Component (b) (Acid Functional Monomers)

Suitable hydrophilic monomers of component (b) are those that areco-polymerisible with the hydrophobic monomer(s) of component (a) andare water soluble. Conveniently the at least one hydrophilic monomer ofcomponent (b) may comprise at least one activated unsaturated moiety asdefined herein.

Usefully the hydrophilic monomer of component (b) is an acid functionalethylenically unsaturated monomer for example an acid functional acrylicmonomer.

It will be understood that when referring to acid functional and/oracidic components herein this may relate to acidic moieties and/orpotential acidic moieties which under the conditions of use may formacidic groups (e.g. anhydrides). An acid bearing monomer could bepolymerised as the free acid or as a salt, e.g. the ammonium and/oralkali metal salt thereof. References herein to acids should thereforealso be understood to include suitable salts and/or derivates thereof(such as anhydrides and/or acid chlorides thereof).

Preferred hydrophilic monomers comprise, advantageously consistessentially of, at least one ethylenically unsaturated carboxylic acidalthough other acid groups such as optionally substituted organophosphoric and/or sulphonic acids may also be used.

Examples include phosphated alkyl(meth)acrylates, sulphonic acids (andderivatives thereof) of arylalkylenes, sulphonic acids (and derivativesthereof) of alkyl(meth)acrylates and/or other organo substitutedsulphonic acids (such as acrylamidoalkyl sulfonic acids).

Preferred arylalkylene sulphonic acids are those where the arylalkylenemoiety comprises optionally hydrocarbo substituted styrene, convenientlyoptionally C₁₋₁₀hydrocarbyl substituted styrene more convenientlyoptionally C₁₋₄alkyl substituted styrene. Useful acids are sulphonicacid substituted derivatives of stryenic compounds selected from thegroup consisting of styrene, α-methyl styrene, vinyl toluene, t-butylstyrene, di-methyl styrene and/or mixtures thereof. Especially preferredis styrene p-sulphonic acid and its corresponding acid chloride styrenep-sulphonyl chloride.

Preferred phosphated organo acids comprise phosphated(meth)acrylatesoptionally substituted for example with one or more hydroxyl groups, forexample phosphated hydroxy(meth)acrylates and C₁₋₄alkyl esters thereof.

Other preferred hydrophilic monomers of component (b) comprises partialacids of multivalent esters, more preferably. half esters of diesters,most preferably mono acid half itaconate esters (i.e. those esters ofFormula A where either R_(a) or R_(b) is H). Itaconic acid is alsoanother example of a (di)acid functional monomer which is also suitableas component (b).

More preferred acids have one ethylenic group and one or two carboxygroups. Most preferably the acid(s) (and/or suitable acid derivative(s)thereof) are selected from the group consisting of: acrylic acid (andcopolymerisable oligomers thereof), beta carboxy ethyl acrylate,citraconic acid, mesaconic acid, crotonic acid, fumaric acid, itaconicacid, maleic acid, methacrylic acid, methylene malonic acid, anhydridesthereof, salts thereof, acid chlorides thereof, combinations thereof inthe same species and/or mixtures thereof.

Especially preferred monomers that may comprise component (b) areselected from:

acrylic acid, methacrylic acid, beta carboxy ethyl acrylate, methylenemalonic acid, maleic anhydride, itaconic acid, itaconic anhydride,phosphated hydroxylethyl methacrylate (phosphated HEMA), phosphatedhydroxylethyl acrylate (phosphated HEA), phosphated hydroxylpropylmethacrylate (phosphated HPMA), phosphated hydroxylpropyl acrylate(phosphated HPA), sulphonated styrene (and its chloride),2-acrylamido-2-methylpropane sulfonic acid (AMPS) andethylmethacrylate-2-sulphonic acid.

Particularly preferred acid monomers are acrylic acid, methacrylic acid,beta carboxy ethyl acrylate, itaconic acid, and/or itaconic anhydride.

For emulsion polymerization acrylic acid, methacrylic acid, beta carboxyethyl acrylate, and/or itaconic acid may be convenient. For SADcopolymerization, acrylic acid, methacrylic acid, and/or itaconicanhydride are preferred.

The hydrophillic monomer component (b) may optionally be absent from thecompositions and/or copolymers of the invention but if present ispresent in an amount of more than a trace amount usefully greater thanor equal to 0.1 wt-%, conveniently greater than or equal to 0.5 wt-%,for example greater than 0.8 wt-% based on the total weight of monomers(a), (b), (c) and (d) used to prepare the copolymer being 100%.

Conveniently component (b) if present is present in the compositionsand/or copolymers of the invention in an amount of less than 23 wt-%,more conveniently less than or equal to 20 wt-%, even more convenientlyless than or equal to 10 wt-%, most conveniently ≦5 wt-%, such as ≦3wt-%; for example ≦1 wt % based on the total weight of monomers (a),(b), (c) and (d) used to prepare the copolymer being 100%.

Preferably, component (b) may be used in a total amount from 0 to 10wt-%, more preferably from about 0.1 to about 5 wt-%, even morepreferably from about 0.1 to about 3 wt-%, most preferably from about0.5 to about 1% by weight based on the total weight of monomers (a),(b), (c) and (d) used to prepare the copolymer being 100%.

Conveniently component (b) may be used in a total amount sufficient thatthe resultant polymer has an acid value (AV) of between 3 and 100 mg KOHper g of solid polymer, preferably from 8 to 80 mg KOH per g, morepreferably from 15 to 65 mg KOH per g, and most preferably from 15 to 45mg KOH per g.

Usefully component (b) satisfies both the acid value (AV) and weightlimits herein, but it will be appreciated that depending on the monomerused the AV specified herein may be achieved using weight percentagesoutside those preferred wt-% values given herein. Where there is anapparent inconsistency herein between any weight % of monomer or othercomponent and the acid values specified it will be appreciated thatsatisfying the AV is generally the more desirable objective. Ifnecessary the values for weight % of the relevant ingredients can bemodified appropriately in a manner well known to a skilled person.

Component (c) (Lower Itaconate Esters and Itaconate Amides)

Component (c) comprises one or more other diester itaconate monomersother than those of Formula 1, preferably a monomer of Formula A whereneither Ra nor Rb are H or an optionally substituted C₄₋₁₀hydrocarbo.More preferably component (c) comprises a lower itaconate diester. Asused herein the term lower itaconate diester denotes diesters of FormulaA where Ra and Rb are independently optionally substitutedC₁₋₃hydrocarbo groups, such as C₁₋₃alkyl, an example of which isdimethyl itaconate (DMI).

Usefully component (c) may comprise lower itaconate diesters (i.e.diesters other than those of Formula 1), and/or higher or loweritaconate amides and thus component (c) may be represented by Formula 2

where R₃ and R₄ independently represent H or an optionally substitutedhydrocarbo moiety having from 1 to 20 carbon atoms (e.g. from 1 to 6carbon atoms); preferably C₁₋₂₀alkyl, preferably C₁₋₆alkyl, morepreferably C₁₋₄alkyl, most preferably C₁₋₃alkyl; X₁ and X₂ independentlyrepresents O or NR₅ where R₅ denotes H or an optionally substitutedhydrocarbo moiety having from 1 to 20 carbon atoms (e.g. from 1 to 6carbon atoms); preferably C₁₋₂₀alkyl, more preferably C₁₋₆alkyl; evenmore preferably C₁₋₄alkyl; for example C₁₋₃alkyl;with the proviso that when X₁ and/or X₂ are O then the respective R₃and/or R₄ attached to the oxy group independently represent anoptionally substituted hydrocarbo having from 1 to 3 carbon atoms,preferably C₁₋₃alkyl.

Components (a), (b), (c) and (d) are mutually exclusive. Thus compoundsof Formula 2 are different from those of Formula 1 and the mono acidhalf itaconate esters are also excluded from Formulae 1 and 2,optionally comprising part of hydrophilic component (b).

Thus in one preferred embodiment of the invention components (a) and (b)(and optionally (c) where present) are each derived from itaconatesand/or acids and/or derivatives thereof, more preferably from abiorenewable source. Thus for example component (a) may be adi(C₄₋₆dialkyl)itaconate, (e.g. DBI), component (b) may be itaconicanhydride itaconic acid, and/or C₁₋₄alkyl monoester of itaconic acid andcomponent (c) where present may be a di(C₁₋₃dialkyl)itaconate (e.g.DMI). In such an embodiment optionally there is no component (d) so thecopolymer may advantageously be obtained from monomers from the sameitaconate source.

Whilst R₃ and R₄ may be different, more conveniently they representidentical moieties.

Whilst X₁ and X₂ may be different, more conveniently they representidentical moieties.

Preferably component (c) may be used in a total amount of less than 35%,more preferably from 0 to 25% by weight.

The component (c) if present may optionally be present in an amountusefully greater than or equal to 0.1 wt-%, conveniently greater than orequal to 0.5 wt-%, for example greater than 1.0 wt-% based on the totalweight of monomers (a), (b), (c) and (d) used to prepare the copolymerbeing 100%.

Conveniently component (c) is present in the compositions and/orcopolymers of the invention in an amount of less than 40 wt-%, moreconveniently less than or equal to 35 wt-%, even more conveniently lessthan or equal to 25 wt-%, most conveniently ≦20 wt-%, for example ≦15 wt% based on the total weight of monomers (a), (b), (c) and (d) used toprepare the copolymer being 100%.

Component (c) may be used in a total amount from 0 to 10 wt-%,preferably from 0.01 to 10 wt-%, more preferably from 0.1 to 40 wt-%,even more preferably from 0.5 to 35 wt-%, most preferably from 1.0 to 30wt-%, for example from 1.0 to 25 wt-% by weight based on the totalweight of monomers (a), (b), (c) and (d) used to prepare the copolymerbeing 100%.

Component (d) (Other Copolymerisable Monomers)

Preferably component (d) comprises monomers not part of components (a),(b) or (c), more preferably that are copolymerisable with them in anysuitable technique such as any of those described herein (for example ina SAD and/or an emulsion polymerisation).

Component (d) may comprise a suitable activated unsaturated moiety (suchas ethylenic unsaturation) where the structure(s) of component (d) donot overlap with any of components (a), (b) or (c).

Preferably component (d) is used in an amount of less than 50% and morepreferably less than 40% by weight.

Component (d) may comprise monomers that can undergo crosslinking, thatcan improve adhesion of the coating to various substrates, that canenhance the colloidal stability of the polymer emulsion, or that can beused to affect Tg, or polymer polarity.

Conveniently component (d) may comprise (meth)acrylate monomers havingalkyl moieties comprising between 1 and 20 carbon atoms, styrene,alpha-methyl styrene, (meth)acrylonitrile, (meth)acryl amide oralkylated(meth)acryl amides, diacetone acryl amide, acetoacetoxyethylmethacrylate, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate,silane functional monomers, such as 3-methacryloxypropyltrimethoxysilane (Geniosil GF31, ex Wacker), ureido functional monomers,such as Plex 6852-O (ex. Evonik), i-bornyl(meth)acrylate,polyethylene(meth)acrylate, polypropylene(meth)acrylate.

Component (d) may also comprise crosslinking monomers that can inducecrosslinking of the copolymer composition. Crosslinking can occur atambient temperatures (using for instance diacetone acryl amide combinedwith adipic dihydrazide), at elevated temperatures (stoving conditionsin which for instance copolymerized hydroxyethyl(meth)acrylate reactswith hexamethoxy methyl melamines), as 2C composition (copolymerizedhydroxyethyl(meth)acrylate reacting with polyisocyanates, such asBayhydur 3100), or as UV coating (when polymers or oligomers havingmultiple unsaturated groups are admixed. Typical examples include di- ortri-functional multifunctional acrylates such as trimethylol propanetriacrylate or ethoxylated or propoxylated versions thereof).

Optionally component (d) may also comprise least one polymerprecursor(s) of Formula 3

where Y denotes an electronegative group,R₆ is H, OH or an optionally hydroxy substituted C₁₋₁₀hydrcarboR₇ is H or a C₁₋₁₀hydrocarbo;R₈ is a C₁₋₁₀hydrocarbo group substituted by at least one activatedunsaturated moiety; and; either:

-   -   A represents a divalent organo moiety attached to both the —HN—        and —Y— moieties so the -A-, —NH—, —C(═O)— and —Y— moieties        together represent a ring of 4 to 8 ring atoms, and R₇ and R₈        are attached to any suitable point on the ring; or        A is not present (and Formula 3 represents a linear and/or        branched moiety that does not comprise a heterocyclic ring) in        which case R₇ and R₈ are attached to R₆; and        m is an integer from 1 to 4.

The ring moiet(ies) of Formula 3 are each attached to R₈ and in Formula3 when m is 2, 3 or 4 then R₈ is multi-valent (depending on the value ofm). If m is not 1 R₇ and —Y— may respectively denote the same ordifferent moieties in each ring, preferably the same respective moietiesin each ring. R₇ and R₈ may be attached at any suitable position on thering.

Preferred monomers of Formula 3 comprise, conveniently consistessentially of, those where: A represents a optional substituteddivalent C₁₋₅hydrocarbylene; and

—Y— is divalent —NR₉— (where R₉ is H, OH, optionally hydroxy substitutedC₁₋₁₀hydrocarbo or R₈) or divalent O,

More preferred monomers of Formula 3 comprise those where: m is 1 or 2

—Y— is —NR₈— (i.e. where Formula 2 is attached to R₈ via a ringnitrogen), A represents a divalent C₁₋₃hydrocarbylene; R₆ is H, R₇ is aC₁₋₁₀hydrocarbo; and

R₈ comprises a (meth)acryloxyhydrocarbo group or derivative thereof(e.g. maleic anhydride).

Monomers represented by Formula 3 include some monomers informallyreferred to as ureido monomers. Further suitable ureido monomers ofFormula 3 are described in “Novel wet adhesion monomers for use in latexpaints” Singh et al, Progress in Organic Coatings, 34 (1998), 214-219,(see especially sections 2.2 & 2.3) and EP 0629672 (National Starch)both of which are hereby incorporated by reference. Conveniently themonomers of Formula 3 may be used as a substantially pure compound (ormixture of compounds) or may be dissolved in a suitable solvent such asa suitable (meth)acrylate or acrylic derivative for example methylmethacrylate.

Other and/or additional component (d) may be used in those cases wherehigher molecular weights are desired, such as suitable multi functional(meth)acrylates or divinyl aromatics. Typical examples include di-,tri-, or tetra-functional (meth)acrylates, especially difunctional(meth)acrylates and divinyl benzene. Typical concentrations are lessthan 10%, more preferred less than 5%, even more preferred between 0.05and 4%, most preferred between 0.1 and 2.5%, and even most preferredbetween 0.15 and 1.5% by weight based on total monomers.

The component (d) may optionally be present in an amount usefullygreater than or equal to 0.1 wt-%, conveniently greater than or equal to0.5 wt-%, for example greater than 1.0 wt-% based on the total weight ofmonomers (a), (b), (c) and (d) used to prepare the copolymer being 100%.

Conveniently component (d) is present in the compositions and/orcopolymers of the invention in an amount of less than 77 wt-%, moreconveniently less than or equal to 50 wt-%, even more conveniently lessthan or equal to 40 wt-%, most conveniently ≦30 wt-%, for example ≦25 wt% based on the total weight of monomers (a), (b), (c) and (d) used toprepare the copolymer being 100%.

Preferably, component (d) may be used in a total amount from 0 to 77wt-%, more preferably from about 0.1% to about 50 wt-%, even morepreferably from about 0.5% to about 40 wt-%, most preferably from about1.0% to about 30% by weight based on the total weight of monomers (a),(b), (c) and (d) used to prepare the copolymer being 100%.

Other Aspects of the Invention

One aspect of the invention relates to an aqueous sequential vinylpolymer dispersion comprising 30% by weight (preferably at least 40%) ofpolymer obtained or obtainable from one or more higher itaconatediester(s).

Another aspect of the invention relates an aqueous vinyl polymer coatingcompositions comprising blends, copolymers and/or mixtures thereof of anoligomeric component and a polymeric component where the polymericcomponent comprises 30% by weight (preferably at least 40%) of materialobtained or obtainable from one or more higher itaconate diester(s).

A yet other aspect of the invention relates vinyl polymer beadscomprising 30% by weight (preferably at least 40%) of polymer obtainedor obtainable from one or more higher itaconate diester(s).

Other examples of suitable monomers that may comprises all or part ofcomponents (a), (b), (c), or (d) may be described in the various furtheraspects of the invention later in this application. It will beunderstood that where suitable such monomers where not already mentionedabove may also be used as components in the above aspect of theinvention.

Polymerisation Processes

Copolymers of the invention may be formed using a number of processes.These include emulsion polymerisation, suspension polymerisation, bulkpolymerisation and solution polymerisation. Such processes are extremelywell known and need not be described in great detail.

In one embodiment emulsion polymerisation is used to form copolymers ofthe invention.

A conventional emulsion process involves dispersing the monomers in anaqueous medium and conducting polymerisation using a free-radicalinitiator (normally water soluble) and appropriate heating (e.g. 30 to120 C.°) and agitation.

The aqueous emulsion polymerisation can be effected with conventionalemulsifying agents (surfactants) being used such as anionic and/ornon-ionic emulsifiers. The amount used is preferably low, preferably 0.3to 2% by weight, more usually 0.3 to 1% by weight based on the weight oftotal monomers charged.

The aqueous emulsion polymerisation can employ conventional free radicalinitiators such as peroxides, persulphates and redox systems as are wellknown in the art. The amount of initiator used is generally 0.05 to 3%based on the weight of total monomers charged.

The aqueous emulsion polymerisation process may be carried out using an“all-in-one” batch process (i.e. a process in which all the componentsto be employed are present in the polymerisation medium at the start ofpolymerisation) or a semi-batch process in which one or more of thecomponents employed (usually at least one of the monomers), is wholly orpartially fed to the polymerisation medium during the polymerisation.Although not preferred, fully continuous processes could also be used inprinciple. Preferably a semi-batch process is employed.

The polymerisation technique employed may be such that a low molecularweight polymer is formed, e.g. by employing a chain transfer agent suchas one selected from mercaptans (thiols), certain halohydrocarbons andalpha-methyl styrene; or catalytic chain transfer polymerisation usingfor example cobalt chelate complexes as is quite conventional.Alternatively a controlled radical polymerisation process can be used,for instance by making use of an appropriate nitroxide or athiocarbonylthio compounds such as dithioesters, dithiocarbamates,trithiocarbonates, and xanthates in order to mediate the polymerizationvia for example a nitrox mediated polymerisation (NMP), a reversibleaddition fragmentation chain-transfer process (RAFT) or atom transferradical polymerization (ATRP).

When the copolymer of the invention is an emulsion polymer it may bemixed with a variety of other polymer emulsions such as those that donot comprise DBI (or higher itaconate esters). Examples of such secondpolymer emulsions can be polyurethane emulsions,polyurethane-poly(meth)acrylate emulsions, alkyd emulsions, polyesteremulsions and/or polyvinyl emulsions. This latter group of copolymeremulsions may comprise oligomer-polymer emulsions, gradient morphologyemulsions, sequentially polymerized emulsions, or single phase copolymeremulsions.

The emulsions according to the description above can be produced viaemulsion polymerization or via a process called solvent assisteddispersion (SAD) polymerization.

When the copolymer emulsion is produced via emulsion polymerization thiscan be according to a single feed process, a sequentially fedmulti-phase copolymerization process, an oligomer supported emulsionpolymerization process or a power feed process, resulting in a gradientparticle morphology.

In the case of solvent assisted dispersion polymerization process, orSAD polymerization, the polymerization is performed in organic solvents.Next, base and/or surfactant are added and the polymer solution isemulsified. Preferably, the solvent is removed via evaporation at theend of the complete process.

SAD polymer emulsions can be produced via as single feed solutionpolymerization or by a sequentially fed multi-phase polymerization. Itis also envisaged that an SAD polymer emulsion, prior or after theoptional removal of the solvent, is used as a seed for an emulsionpolymerization stage. In this case, the polymer emulsion preparedaccording to the SAD process is used as seed in a batch or semi-batchpolymerization process.

The preferred polymerization process is emulsion polymerization.

Preferably, the weight average molecular weight (M_(w)) (as determinedwith GPC as described herein) of the DBI containing copolymers is morethan 2000 g/mol, more preferably more than 10,000 g/mol, even morepreferably more than 25,000 g/mol, most preferably more than 40,000g/mol, and even most preferably more than 100,000 g/mol.

In the case of oligomer-polymer emulsions prepared via emulsionpolymerization lower molecular weights may be desired. In those caseschain transfer agents may be employed. Typical chain transfer agents canbe mercaptans, such as lauryl mercaptan, i-octyl thioglycolate, or3-mercapto propionic acid, or halogenides, such as bromomethane,bromoethane. Typical chain transfer concentrations in these cases areenough to reduce the weight average molecular weight of the oligomerphase to between 500 and 100,000 g/mol, more preferred between 1,000 and60,000 g/mol, even more preferred between 2,500 and 50,000 g/mol, andmost preferred between 5,000 and 25,000. Typical chain transfer agentconcentrations are below 5%, more preferably below 2.5%, and mostpreferably between 0.5 and 2.5% by weight of total monomer. In the casethat the oligomer is combined with a high molecular weight polymer, thepreferred molecular weights for the high molecular weight fraction willbe as described earlier.

In those cases where the copolymer emulsion comprises multiple phases oris made up from multiple monomer feeds (sequential, oligomer-polymer orpower feed) one of the copolymer phases preferably comprises between 10and 80%, more preferably between 15 and 50%, and most preferably between20 and 40% by weight of the total monomers used to prepare thesequential, power feed, and/or oligomer-polymer composition. Thisparticular copolymer phase has a Tg, as calculated using the Foxequation, of higher than 40° C., more preferably higher than 60° C., andmost preferably higher than 80° C. The other copolymer phase(s) may thencomprise between 20 and 90% of the total monomers more preferablybetween 50 and 85%, and most preferably between 60 and 80% by weight ofthe total monomers used to prepare the sequential, power feed, and/oroligomer-polymer composition. These particular copolymer phase(s) have aTg, as calculated using the Fox equation, of less than 40° C., morepreferably of less than 20° C., and most preferably of less than 0° C.

The difference in Tg in such emulsions between that of the high Tgphase(s) and that of the low Tg phase(s) is preferably at least 20° C.,more preferably at least 30° C., and most preferably at least 40° C.

In a special case it is envisaged that the itaconic anhydride which iscopolymerized in an SAD copolymerization process can be post modifiedusing chemicals having anhydride reactive groups. The objective in thesecases is to introduce special functionalities, such as crosslinking oradhesion promoting groups, while maintaining an acid group that can beused for colloidal stabilization.

Modification of the anhydride groups can occur with any nucleophilicfunctionality. Preferred functionalities include hydroxyl groups,hydrazide groups, hydrazine groups, semi-carbazide groups and aminegroups. In all cases, modification will result in the introduction ofthe moiety attached to the hydroxyl, hydrazide, hydrazine,semi-carbazide or amine group and, simultaneously, of an acid group. Theacid group can subsequently be used for emulsifying the copolymer.

The modification can be done with monofunctional hydroxyl groups,hydrazide, or hydrazine, or primary, or secondary amines, but also withdi-functional or higher functional hydroxyl, hydrazine, hydrazide,semi-carbazide, or primary or secondary amines. Potential hydroxylfunctionalities can include C1-C20 aliphatic, aromatic, orcycloaliphatic mono-, di-, or high functional alcohols. The aliphatic,aromatic, or cycloaliphatic groups can include other functionalitiesthat can, for instance, be used for improved adhesion, crosslinking orother purposes. Typical examples of such functionalities can includephosphate, phosphonate, sulphate, sulphonate, ketone, silane, (cyclic)ureido, (cyclic) carbonate, hydrazide, hydrazine, semi-carbazide,urethane, urea, carbamate, and melamine

The preferred (poly)amines, (poly)hydrazines, or (poly)hydrazides can becharacterized by the same description.

In the case where the copolymer composition is prepared via emulsionpolymerization, the pH of the emulsion can preferably be increased usingorganic or inorganic bases. Typical examples include ammonia, primaryand secondary organic amines, lithium hydroxide, sodium hydroxide orpotassium hydroxide, sodium carbonate or sodium bicarbonate. Typically,the pH is increased only at the end of the manufacturing process,although it can be envisaged that either at the start of thepolymerization the pH of the aqueous phase is already increased(buffered) or that the pH of a polymerizing mixture is increased forinstance between sequential monomer feeds. In the case of copolymersprepared via emulsion polymerization the pH is preferably increased atthe end of the manufacturing process, preferably using ammonia orlithium hydroxide.

Typically, the pH is raised to values above 5, more preferred above 6,and most preferred to values of between 6 and 9.

When the copolymer emulsion is prepared via the SAD polymerizationprocess, emulsification can be done by addition of surfactants, but ispreferably done by first neutralizing the polymer acid groups. This canbe done by addition of base to the solution polymerized polymer followedby the addition of water or by addition of base to an aqueous phasefollowed by the addition of the polymer solution. In both cases,suitable bases are the same as above. Preferred bases are ammonia,lithium hydroxide or dimethyl ethanol amine, diethanol methyl amine,diethanol ethyl amine, diethyl ethanol amine and the like. Typically,the molar ratio of base to acid groups is between 0.5 and 1.3, morepreferred between 0.6 and 1.2, most preferred between 0.6 and 1.

The concentration of volatile organic compounds (VOC) in the aqueouscopolymer emulsions is preferably low. In a preferred case, the VOClevel is below 20 wt-%, more preferred below 10 wt-%, even morepreferred below 5 wt-%, most preferred below 1 wt-%, and even mostpreferred below 0.5 wt-%. Intentionally, the VOC level of the copolymeremulsions, prior to formulating them into paints, is close to 0 wt-%,typically below 0.1 wt-%.

When the copolymer composition is prepared via SAD polymerization,solvents are required for the solution polymerization process. Typicalsolvents include organic solvents that are well known to thoseexperienced in the field, such as acetone, methyl ethylketone, ethanol,methanol, i-propanol, i-octyl alcohol, xylene, glycol ethers, glycolesters. Preferably solvents are used that—following polymerization atelevated pressure—can be removed from the emulsion by evaporation.Preferred solvents in this respect are acetone and methyl ethylketone.

Initiators are required to start the radical polymerization. These, too,are well known to those experienced in the field. The aqueous emulsionpolymerisation can employ conventional free radical initiators such asperoxides, persulphates and redox systems. Useful examples includeinorganic peroxides, such as ammonium persulphate, sodium persulphate,potassium persulphate, AZO initiator, such as azobisisobutyronitrile(AIBN), 2,2′-azodi(2-methylbutyronitrile) (AMBN), and organic peroxideand hydroperoxides, (Hydro)peroxide can readily be used in combinationwith suitable reducing agents. Preferably, initiators are used in anamount of between 0.05 and 6%, more preferably between 0.5 and 4%, mostpreferably from 0.5 to 3% by weight of the total monomers.

Surfactants are used in emulsion polymerization as known to thoseskilled in the art. Typical surfactants have been extensively describedin all kinds of patent applications. The choice and concentration ofsurfactants are not deemed to be critical for this invention. Theaqueous emulsion polymerisation can be effected with conventionalemulsifying agents (surfactants) being used such as anionic and/ornon-ionic emulsifiers. The amount used is preferably low, preferably 0.3to 2% by weight, more usually 0.3 to 1% by weight based on the weight oftotal monomers charged to make the polymer.

In the case of SAD copolymer emulsions, emulsification can be aided byselecting the right anionic, nonionic and mixed anionic/nonionicsurfactant(s). Typically, surfactant is used in an amount of less than5% more preferably less than 3%, and most preferably between 0.2 and2.5% by weight of the total monomers.

Preferably (and subject to the provisos herein) in one embodiment of theinvention the process of making a copolymer emulsion of the inventioncomprises using a chaser monomer composition as described inWO2011073417. In another embodiment a chaser monomer may optionally notbe used.

In a preferred case the residual monomer content of the copolymeremulsion is below 2000 mg/L, more preferred below 1500 mg/L, mostpreferred below 1000 mg/L, and especially preferred below 550 mg/L.

The aqueous coating composition yields coatings with typical Könighardness values of at least 30 s, more preferred at least 40 s, evenmore preferred at least 50 s, and most preferred at least 60 s.

In another embodiment the polymer of the invention may be made using abulk polymerisation process. Bulk polymerisation of olefinicallyunsaturated monomers is described in detail in EP 0156170, WO82/02387,and U.S. Pat. No. 4,414,370 the contents of which are herebyincorporated by reference.

In general in a bulk polymerisation process a mixture of two or moremonomers are charged continuously into a reactor zone containing moltenvinyl polymer having the same ratio of vinyl monomers as the monomermixture. The molten mixture is maintained at a preset temperature toprovide a vinyl polymer of the desired molecular weight. The product ispumped out of the reaction zone at the same rates as the monomers arecharged to the reaction zone to provide a fixed level of vinyl monomerand vinyl polymer in the system. The particular flow rate selected willdepend upon the reaction temperature, vinyl monomers, desired molecularweight and desired polydispersity.

For polymers of the invention especially those to be used in coatingcompositions, providing amino functional groups thereon may also beuseful as such groups provide enhanced adhesion to certain substrates,such as wood and alkyd resins. Amino groups may be incorporated into apolymer by using a carboxyl functional precursor for example prepared byemploying ethylenically unsaturated acid functional monomer(s) such asacrylic acid or methacrylic acid. At least some of thecarboxy-functional groups may be converted to amino groups (as part ofamino ester groups) by reaction with alkylene imines such as ethyleneimine, propylene imine or butylene imine. Such a reaction is wellestablished in the art, being known as an imination reaction and thedetails of this are for example taught in U.S. Pat. No. 7,049,352 thecontents of which are hereby incorporated herein by reference. Thereforea further aspect of the invention comprises iminated versions of the allthe copolymers of the present invention as described herein.

If it is desired to crosslink polymers (for example in a polymerdispersion), the relevant polymers can carry functional groups such ashydroxyl groups and the dispersion subsequently formulated with acrosslinking agent such as a polyisocyanate, melamine, or glycoluril; orthe functional groups on one or both polymers could include keto oraldehyde carbonyl groups and the subsequently formulated crosslinker instep c) could be a polyamine or polyhydrazide such as adipic aciddihydrazide, oxalic acid dihydrazide, phthalic acid dihydrazide,terephthalic acid dihydrazide, isophorone diamine and4,7-dioxadecane-1,10 diamine. It will be noted that such crosslinkingagents will effect crosslinking by virtue of forming covalent bonds.

Another aspect of the invention is described as follows including thespecific additional and/or sub-problems it is designed to address andadditional prior art.

Traditional coatings may be unsatisfactory because the polymer filmspossess little flexibility and the coatings on substrates, such as wood,which are not dimensionally stable; tear and chip off. A disadvantage ofhard polymer dispersions is that they can only be processed with theaddition of large amounts of film formation assistants that aredisadvantageous to initial block resistance.

The initial block resistance is the tendency of the freshly appliedcoatings which have dried for only a short time to block. This tendencyto block makes it virtually impossible, for example, for coatedsubstrates to be stacked rapidly, and is due to the large amounts offilm formation assistants which are still present in the binder film andare released only gradually by the conventional polymers at roomtemperature. When drying is carried out at room temperature, the finalblock resistance is frequently reached only after several days.

EP 387664 discloses an aqueous synthetic resin dispersion having aminimum film forming temperature below 50° C. containing an emulsionpolymer with a core/shell structure consisting of A) 65-90 percent byweight of a weakly crosslinked core polymer having a glass transitiontemperature below 0° C. and an extension at break of at least 150percent and B) 10-35 percent by weight of an essentially non-crosslinkedshell polymer having a glass transition temperature below 60° C., theglass transition temperature of said core polymer being at least 10° C.below that of said shell polymer.

U.S. Pat. No. 5,021,469 discloses a binder, for water based gloss paintscontains, dispersed in a aqueous phase, particles of a multiphaseemulsion polymer made up of (a) core material having a glass transitiontemperature exceeding 40° C. and (b) a shell material having a glasstransition temperature of less than 70° C.

U.S. Pat. No. 4,654,397 discloses a process for the preparation ofaqueous polymer dispersions which have a low film-forming temperaturebut still give films having a high block resistance, and the use ofthese polymer dispersions as binders for coating materials.

None of the above-discussed disclosures teaches a dispersion having theselected combination of features and integers as defined below toproduce the advantageous combination of properties as discussed above.

This aspect of the invention has as its preferred object to provide aphysically-drying binder in the form of an aqueous synthetic resindispersion which physically dries at low temperatures to give highlyelastic films which are more or less non-tacky from the beginning.

The emulsion polymers according to this aspect of the invention addresssome or all of the problems described herein.

The designation of the polymer phase involved as a first phase or corematerial and second phase or shell material does not mean that theinvention should be bound by any particular morphology of the latexparticles. The term polymer phase is to be understood as meaning aportion of the emulsion polymer which is prepared during atemporally-limited segment of the emulsion polymerization and thedispersion of which differs from that of the foregoing or followingphase. This is also known as a multi-stage polymerization.

The two-phase structure of the dispersions of the invention influencesthe properties of the film formed when the dispersion dries aftercoating a substrate.

This aspect of the invention provides an aqueous vinyl polymerdispersion with an advantageous combination of MFFT and anti-blockingproperties which can be prepared at least in part from bio-renewablemonomers (such as biorenewable DBI).

According to this aspect of the present invention there is provided anaqueous polymer dispersion having a minimum film forming temperaturebelow 50° C., more preferably below 30° C. comprising a vinyl polymerderived from olefinically unsaturated monomers, with at least two phasescomprising:

-   -   A) 40 to 90 wt-%, more preferably 50 to 85 wt-% and especially        60 to 80 wt-% of a vinyl polymer A having a glass transition        temperature in the range of from −(minus) 50 to 30° C.; and    -   B) 10 to 60 wt-%, more preferably 15 to 50 wt-% and especially        20 to 40 wt-% of a vinyl polymer B having a glass transition        temperature the range of from 50 to 130° C.; where        -   (i) at least one of the monomers used to prepare vinyl            polymer A and/or vinyl polymer B is represented by Formula 1            as described herein (usefully a higher itaconate ester such            as DBI) preferably in an amount from 20 to 80 wt-%, more            preferably from 20 to 65 wt-%, most preferably 30 to 55 wt-%            of the total monomers        -   (ii) optionally 10% by weight (preferably at least 20 wt-%)            of the total amount of monomer used to form vinyl polymer A            and vinyl polymer B is derived from at least one            bio-renewable olefinically unsaturated monomer;    -   where the weight percentage of monomers in A and B are        calculated in (i) and (ii) based on the total amount of        olefinically unsaturated monomers used to prepare polymer A and        polymer B being 100%;        -   (iii) vinyl polymer A comprises 0.1 to 10 wt-% of at least            one acid-functional olefinically unsaturated monomer where            the weight percentage of acid functional monomer is            calculated based on the total amount of olefinically            unsaturated monomer used to prepare polymer A being 100%.

In this aspect of the invention features (i) and (iii) correspondrespectively to components (a) and (b) of the present invention and theother monomers used to prepare polymers A and B corresponding tooptional components (c) and/or (d) as appropriate.

Other preferred features of this aspect of the present invention aregiven below and/or in the claims.

The acid-functional olefinically unsaturated monomer may be selectedfrom the group consisting of acrylic acid, methacrylic acid, itaconicanhydride, maleic anhydride methylene malonic acid, itaconic acid,crotonic acid and fumaric acid.

Vinyl polymer A may comprise 0.1 to 20 wt-% of at least one crosslinkingolefinically unsaturated monomer, preferably 0.4 to 6 wt-% of at leastone olefinically unsaturated monomer with a wet-adhesion promotingfunctionality.

The crosslinking monomer(s) and wet adhesion promoting monomer(s) can beused together in the same polymer composition. It is, however, oftendesired to use either crosslinking monomer(s) or wet adhesion promotingmonomer(s) in any phase. This means that vinyl polymer A can comprisecrosslinking monomer(s) or wet adhesion promoting monomer(s), whilevinyl polymer contains wet adhesion promoting monomer(s) or crosslinkingmonomer(s). In addition to this it is also possible to use wet adhesionpromoting monomer(s) in either vinyl polymer A and/or vinyl polymer B orin both and no crosslinking monomer(s) or to use crosslinking monomer(s)in vinyl polymer A and/or vinyl polymer B and no wet adhesion promotingmonomer(s).

Olefinically unsaturated monomer with a wet-adhesion promotingfunctionality contain wet-adhesion promoting functional groups such asacetoacetoxy groups and optionally substituted amine or urea groups, forexample cyclic ureido groups, imidazole groups, pyridine groups,hydrazine or semicarbazide groups.

The bio-renewable olefinically unsaturated monomers may comprisebio-renewable (meth)acrylic acid and or bio-renewablealkyl(meth)methacrylate.

The bio-renewable olefinically unsaturated monomers may also comprisebio-renewable: α-methylene butyrolactone, α-methylene valerolactone,α-methylene γ-R¹ butyrolactone (R¹ can be an optionally substitutedalkyl or optionally substituted aryl); itaconates such as dialkylitaconates and monoalkyl itaconates, itaconic acid, itaconic anhydride,crotonic acid and alkyl esters thereof, citraconic acid and alkyl estersthereof, methylene malonic acid and its mono and dialkyl esters,citraconic anhydride, mesaconic acid and alkyl esters thereof.

The bio-renewable monomers may also comprise bio-renewable: N—R²,α-methylene butyrolactam (R² can be an optionally substituted alkyl oroptionally substituted aryl); N—R², α-methylene γ-R¹ butyrolactam;N-alkyl itaconimids; itaconmonoamids; itacondiamids; dialkylitaconamides, mono alkyl itaconamides; furfuryl(meth)acrylate; and fattyacid functional (meth)acrylates.

Vinyl polymer A and vinyl polymer B may comprise at least about 1.5dpm/gC of carbon-14.

In a further aspect of the present invention provides a process forpreparing the aqueous polymer dispersion (or polymer A and polymer B asdescribed above)

which process comprises steps:

-   -   a) a first polymerization step, to form a first phase vinyl        polymer;    -   b) a second polymerization step in the presence of the resulting        first phase vinyl polymer from step a) to form a second phase        vinyl polymer.

Vinyl polymer A may be the first phase in which case vinyl polymer B isthe second phase. Alternatively vinyl polymer B may be the first phasein which case vinyl polymer A is the second phase. Preferably vinylpolymer A is the first phase. Preferably the second phase vinyl polymeris prepared in the presence of the first phase vinyl polymer.

Optionally the process includes c) a neutralisation step before/after orduring step c) to solubilise the first polymer phase.

Optionally the process includes d) the addition of a crosslinking agentafter the polymerization step a) and/or step b), said crosslinking agentbeing reactable with any crosslinking functional groups of vinyl polymerA and/or vinyl polymer B on subsequent drying of the coating dispersionto effect covalent bond crosslinking.

Optionally the process includes a post treatment imination step e) withalkylene imines like for instance propylene imine) which can greatlyimprove wet adhesion.

A film, polish, varnish, lacquer, paint, ink and/or adhesive maycomprise the aqueous polymer dispersion comprising polymer A and polymerB described above and these aqueous polymer dispersions may also be usedprotective coatings on wood, plastic, paper and/or metal substrates.

An embodiment of the invention provides an aqueous polymer dispersionwhere vinyl polymers A and B comprise individually at least 30 wt-%,more preferably at least 40 wt-%, most preferably at least 60 wt-%, andespecially preferably at least 70 wt-% of compounds of Formula 1 such ashigher itaconate diesters for example DBI. Although the concentration ofitaconate monomers in polymers A and B can be similar, it is preferredthat the concentrations are different. In each of the preferred casesdescribed above, it is envisaged that the concentration of itaconatemonomers in the other phase can always be below 20 wt-% or even be 0wt-%.

Preferably the concentration of itaconate esters according to theinvention in the low Tg phase is at least 10 wt-% higher than that inthe high Tg phase, more preferably at least 20 wt-%.

In yet another preferred embodiment of the invention there is providedan aqueous polymer emulsion according to the invention where the monomerfeed making up polymer A or the feed making up polymer B comprise up to20 wt-% of organic solvent, more preferably less than 10 wt-%, even morepreferably less than 5 wt-%, and most preferably between 0.1 and 2.5wt-%.

Improved properties of the copolymers of the this aspect of theinvention may include heat resistance, colloidal stability, pigmentcompatibility, surface activity, blocking resistance and reduced MFFTdepending on the monomers used.

The monomer system used for the preparation of vinyl polymer A and vinylpolymer B is any suitable combination of olefinically unsaturatedmonomers which is amenable to copolymerisation (including bio-renewablemonomers described herein which may of course also be acid-functional,crosslinkable etc at described below).

Preferably vinyl polymer A comprises 0.5 to 9 wt-%, more preferably 1 to8 wt-% and especially 1.5 to 5 wt-% of at least one acid-functionalolefinically unsaturated monomer.

Preferably vinyl polymer B comprises less than 5 w % of any acidfunctional monomers and preferably less than 2 w %, and in somepreferred embodiments none at all.

Other, non-acid functional, non-crosslinking monomers which may becopolymerized with the acid monomers include acrylate and methacrylateesters and styrenes; also dienes such as 1,3-butadiene and isoprene,vinyl esters such as vinyl acetate, and vinyl alkanoates. Methacrylatesinclude normal or branched alkyl esters of C1 to C12 alcohols andmethacrylic acid, such as methyl methacrylate, ethyl methacrylate, andn-butyl methacrylate, and (usually C5 to C12) cycloalkyl methacrylatesacid such as isobornyl methacrylate and cyclohexyl methacrylate.Acrylates include normal and branched alkyl esters of C1 to C12 alcoholsand acrylic acid, such as methyl acrylate, ethyl acrylate, n-butylacrylate, and 2-ethylhexyl acrylate, and (usually C5-C12) cycloalkylacrylates such as isobornyl acrylate and cyclohexylacrylate. Alsoincluded are (meth)acrylamide, and mono- or di-alkyl amides of(meth)acrylic acid. Styrenes include styrene itself and the varioussubstituted styrenes, such as .alpha.-methyl styrene and t-butylstyrene. Nitriles such as acrylonitrile and methacrylonitrile may alsobe polymerised, as well as olefinically unsaturated halides such asvinyl chloride, vinylidene chloride and vinyl fluoride.

Functional monomers which impart crosslinkability (crosslinking monomersfor short) include epoxy (usually glycidyl) and hydroxyalkyl (usuallyC1-C12, e.g. hydroxyethyl)methacrylates and acrylates, as well as ketoor aldehyde functional monomers such as acrolein, methacrolein and vinylmethyl ketone, the acetoacetoxy esters of hydroxyalkyl (usually C1-C12)acrylates and methacrylates such as acetoacetoxyethyl methacrylate andacrylate, and also keto-containing amides such as diacetone acrylamide.The purpose of using such functional monomer is to provide subsequentcrosslinkability in the resulting polymer system as discussed. Inprinciple the functional monomer used for imparting crosslinkabilitycould be acid-bearing monomer, but this is not usual.

Preferably vinyl polymer A comprises 0.1 to 3 wt-% of at least onecrosslinking monomer containing at least two olefinically unsaturatedgroups.

Preferably vinyl polymer A comprises 0.1 to 20 w %, preferably 1 to 15 w%, and particularly 1 to 10 w % of crosslinking monomers.

Adhesion promoting monomers include amino, urea, or N-heterocyclicgroups. As known to those skilled in the art this property can also beachieved by imination i.e. reaction of the acid groups with propyleneimine.

Preferably vinyl polymer A comprises 0.4 to 6 wt-% of at least oneolefinically unsaturated monomer with a wet-adhesion promotingfunctionality, more preferably between 0.5 and 4 wt-%.

Vinyl polymer A preferably has a weight average molecular weight (M_(w))as determined with GPC of from 20,000 to 6,000,000 g/mol, preferablymore than 80,000 g/mol and most preferably more than 100,000 g/mol. Morepreferably the upper limit does not exceed 4,000,000 g/mol.

Vinyl polymer B preferably has a weight average molecular weight (M_(w))as determined with GPC of from 20,000 to 6,000,000 g/mol, preferablymore than 80,000 g/mol and most preferably more than 100,000 g/mol. Morepreferably the upper limit does not exceed 4,000,000 g/mol.

Preferably vinyl polymer A has a glass transition temperature in therange of from −(minus) 20 to 20° C.

Preferably vinyl polymer B has a glass transition temperature in therange of from 65 to 110° C.

Preferably the polymer dispersion contains latex particles having adiameter from 30 to 900 nanometers (nm), particularly 60 to 300 nm. Theparticle size distribution can be unimodal, bimodal, or polymodal.Dispersions having bi- or poly-modal particle size distributions can bemade according to the method described in DE3147 008 or U.S. Pat. No.4,456,726.

In a preferred embodiment there is provided an aqueous polymerdispersion having a minimum film forming temperature of below 30° C.comprising a vinyl polymer derived from olefinically unsaturatedmonomers, with at least two phases comprising:

-   -   A) 60 to 80 wt-% of a vinyl polymer A having a glass transition        temperature in the range of from −20 to 20° C.; and    -   B) 20 to 40 wt-% of a vinyl polymer B having a glass transition        temperature the range of from 65 to 110° C.;        wherein vinyl polymer A comprises 2 to 5 wt-% of at least one        acid-functional olefinically unsaturated monomer, and        wherein at least 50 wt-% of the monomer composition used to form        vinyl polymer A and vinyl polymer B comprises itaconate diesters        of Formula 1, preferably from a biorenewable source.

If vinyl polymer A is made in the second phase then preferably vinylpolymer A has at least 80%, more preferably at least 100% and mostpreferably 110% of the acid value of vinyl polymer B being made in thefirst phase and this helps to affect the morphology of the particles toget good film formation.

According to an embodiment of the invention there is also provided aprocess to obtain an aqueous polymer dispersion as defined herein whichprocess comprises steps:

-   -   a) a first polymerization step, to form a first phase vinyl        polymer;    -   b) a second polymerization step in the presence of the resulting        first phase vinyl polymer from step a) to form a second phase        vinyl polymer.

The first phase vinyl polymer may be formed using emulsionpolymerisation. Such processes are extremely well known, are describedelsewhere in this specification and need not be described further greatdetail.

If desired the pH of the polymer emulsion can be adjusted to highervalues using suitable bases. Examples of which include organic aminessuch as trialkylamines (e.g. triethylamine, tributylamine), morpholineand alkanolamines, and inorganic bases such as ammonia, NaOH, KOH, andLiOH.

In an embodiment of the invention it is also possible to use a gradientpolymerisation process as described in for example EP1434803 to make atleast part of the first and second phase. The second phase monomer feedpreferably starts after 20 to 80% completion of the first phase monomerfeed.

In a preferred embodiment when >30 wt-% of monomers of Formula 1 (suchas DBI) are used the monomers are preferably fed into the reactor duringpolymerisation, with a preferred feed time>60 minutes, morepreferably >120 minutes and most preferred >150 minutes.

Preferably, the concentration of unreacted monomer according to Formula1 during the polymerisation is less than 5 wt-% on total weight of theemulsion, more preferably less than 3 wt-%, most preferably less than 1wt-%, and typically less than 0.5 wt-% on total weight of the emulsion.The concentration of unreacted monomer(s) other than according toFormula 1 during the polymerisation is less than 5 wt-%, more preferredless than 2.5 wt-%, most preferably less than 1 wt-%, and typically lessthan 0.3 wt-% on total weight of the emulsion.

Preferably the dispersions of the invention have VOC levels of less than100 g/L and more preferably less than 80 g/L, most preferably less than50 g/L and especially less than 20 g/L of volatile organic components(VOC) such as coalescing solvents.

If crosslinking monomers are present then preferably the amount ofcrosslinking agent that is employed is such that the ratio of the numberof crosslinker groups present in the first phase vinyl polymer and (ifemployed) in the second phase vinyl polymer to the number of reactivegroups (for crosslinking purposes) in the crosslinking agent is withinthe range of from 10/1 to 1/3, preferably 2/1 to 1/1.5.

A crosslinker reactive with a copolymerised crosslinking monomer, ifpresent, is usually combined with the aqueous dispersion by adding itthereto after the preparation of the second phase vinyl polymer (andsometimes just before use of the dispersion), although it may inprinciple also be combined by performing the polymerisation of thesecond phase vinyl polymer in the presence of the crosslinking agent. Acombination of both incorporation expedients may also in principle beused.

It will be appreciated that vinyl polymer A and optionally vinyl polymerB possess functional groups for imparting latent crosslinkability to thedispersion (i.e. so that crosslinking takes place e.g. after theformation of a coating therefrom) when combined with the crosslinkingagent. For example, one or both polymers could carry functional groupssuch as hydroxyl groups and the dispersion subsequently formulated witha crosslinking agent such as a polyisocyanate, melamine, or glycoluril;or the functional groups on one or both polymers could include keto oraldehyde carbonyl groups and the subsequently formulated crosslinker instep c) could be a polyamine or polyhydrazide such as adipic aciddihydrazide, oxalic acid dihydrazide, phthalic acid dihydrazide,terephthalic acid dihydrazide, isophorone diamine and4,7-dioxadecane-1,10 diamine. It will be noted that such crosslinkingagents will effect crosslinking by virtue of forming covalent bonds.

According to an embodiment of the invention there is provided a processfor the production of the aqueous polymer coating dispersion, whichprocess comprises steps: a′) a first polymerization step, to form afirst phase vinyl polymer; b′) a second polymerization step in thepresence of the resulting first phase vinyl polymer from step a′) toform a second phase vinyl polymer. Optionally the process includes c′) aneutralisation step before/after or during step b′). Optionally theprocess includes a post treatment imination step d′) with alkyleneimines like for instance propylene imine) which can greatly improve wetadhesion. Optionally the process includes e′) the addition of acrosslinking agent after the polymerization step a′) and/or step b′),and preferably after the optional imination step d′), said crosslinkingagent being reactable with any crosslinking functional groups of vinylpolymer A and/or vinyl polymer B on subsequent drying of the coatingdispersion to effect covalent bond crosslinking (as described herein).

A still another aspect of the invention is described as followsincluding the specific additional and/or sub-problems it is designed toaddress and additional prior art.

There is an ever increasing demand to replace or supplementsolvent-based polymer coating compositions with aqueous-basedcounterparts due to the environmental toxicity and flammability problemsposed by the use of volatile organic solvents. However, even whereaqueous-based polymer compositions have been devised, their productionhas usually entailed the intermediate use of organic solvents, requiringsubsequent removal, or the incorporation of a certain amount of asolvent in the final composition which acts to ensure properfilm-formation on coating (known as a coalescing solvent). There istherefore also now increasing pressure to significantly reduce oreliminate the volatile organic content (VOC) in aqueous-based polymercomposition syntheses and also provide biorenewable monomers.

In addition, even if one can achieve a solvent-free aqueous polymercoating composition, it has been found difficult to achieve one with abalance of good properties conventionally required in most coatingcompositions, particularly acceptably high hardness and low minimum filmforming temperature (MFFT) of the resulting coating. The coating shouldalso have good water and solvent resistance.

EP0758364 discloses a process for making organic solvent-free aqueouscross-linkable polymer composition comprising an acid-functional polymerA with Tg 10 to 125° C. and having cross-linker functional groups and apolymer B having Tg at least 25° C. below that of polymer A incombination with a crosslinking agent having an advantageous balance ofMFFT and Koenig hardness.

EP0758347 discloses a process for making organic solvent-free aqueouscross-linkable polymer composition comprising an acid-functional polymerA with Tg less than 50° C. and having cross-linker functional groups anda polymer B having Tg at least 25° C. above that of the polymer A incombination with a crosslinking agent having an advantageous balance ofMFFT and Koenig hardness.

None of the above-discussed disclosures teaches a vinyl polymer coatingcomposition having the selected combination of features and integers asdefined in the invention below and an advantageous combination ofproperties as discussed above, using monomers such as DBI (optionallyfrom a biorenewable source) to make the vinyl polymer.

In this aspect of the invention we provide an aqueous vinyl polymercoating composition with an advantageous combination of MFFT andhardness and which furthermore is prepared at least in part from amonomer of Formula 1 (such as di(n-butyl) itaconate (DBI)), preferablyderived from a bio-renewable source.

According to this aspect of the present invention there is provided anaqueous vinyl polymer coating composition comprising at least:

α[alpha]) a vinyl polymer C (optionally corresponding to oligomercomposition O), comprising:

-   -   i) 1 to 45 wt-% of acid-functional olefinically unsaturated        monomers;    -   ii) 0 to 20 wt-% of crosslinking-functional olefinically        unsaturated monomers; and    -   iii) 99 to 50 wt-% of non-acid functional, non-crosslinking        monomers selected from the group consisting of olefinically        unsaturated monomers and aryl arylalkylene monomers;        where the weight percentages of each of (α[alpha])(i),        (α[alpha])(ii) and (α[alpha])(iii) are calculated based on the        total of (α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii)=100%; and        where        said polymer C having a molecular weight within the range of        from 1,000 to 150,000 g/mol and an acid value>5 mgKOH/g; and        (β[beta])) a vinyl polymer D (optionally corresponding to        polymer composition P), comprising:    -   i) 0 to 10 wt-%, preferably less than 25 wt-%, of at least one        acid-functional olefinically unsaturated monomer;    -   ii) 0 to 25 wt-%, preferably less than 25 wt-%, of        crosslinking-functional olefinically unsaturated monomers; and    -   iii) 0 to 100-wt-% of non-acid functional, non-crosslinking        monomers selected from the group consisting of olefinically        unsaturated monomers and aryl arylalkylenemonomers other than a        monomer of Formula 1        at least one of β[beta] (i) to (iii) being present; where        the weight percentages of each of (β[beta])(i), (β[beta])(ii),        (β[beta])(iii) and (β[beta]) (iv) are calculated based on the        total of        (β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)=100%;        and where        said polymer D has a molecular weight (M_(w)), as determined by        GPC, of at least 80,000 g/mol and an acid value less than 65        mgKOH/g, preferably less than 50 mgKOH/g; more preferably less        than 30 mgKOH/g, most preferably less than 20 mgKOH/g, for        example less than 10 mgKOH/g        wherein    -   I) the weight % of the monomers used to form polymer C        (α[alpha])(i), (α[alpha]) (ii), and (α[alpha])(iii)=polymer C        monomers) and polymer D (W[beta])(i), (β[beta])(ii),        (β[beta])(iii) and (β[beta])(iv)=polymer D monomers) when        calculated based on the total amount of        (α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii)+β[beta](i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)=100%        have the weight percentages of:        -   for polymer C monomers from 5 to 75%, preferably 5 to 70%;            and        -   for polymer D monomers from 25% to 95%, preferably from 30%            to 90%    -   II) from 20 to 75 wt-%, preferably from 24 to 60 wt-%, by weight        of the total amount of monomers        (α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii)+(β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)        used to form polymer C and polymer D comprises at least one        monomer of Formula 1 (for example DBI);    -   III) optionally at least 10%, preferably at least 20%, by weight        of the total amount of monomers        (α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii)+(β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)        used to form polymer C and polymer D is derived from at least        one bio-renewable olefinically unsaturated monomer;    -   IV) the acid value of polymer C is greater than the acid value        of polymer D by at least 10 mgKOH;    -   V) polymer C and polymer D have a glass transition temperature        difference of at least 20° C.;    -   VI) polymer C is prepared in the presence of polymer D;    -   VII) said coating composition on drying has a Koenig hardness of        at least 20 sec; and    -   VII) said coating composition has a minimum film forming        temperature of <55° C.

Preferably polymer C is an oligomer and polymer D is a non-oligomericpolymer.

In this aspect of the invention, feature (β[beta])(iv) corresponds tocomponent (a) of the present invention; features (α[alpha])(i) and(β[beta])(i) correspond to component (b) of the present invention, andthe remaining features (α[alpha])(ii), (α[alpha])(iii), (β[beta])(ii)and (β[beta])(iii) correspond as appropriate to optional components (c)and/or (d) of the present invention.

Other preferred features of this aspect of the present invention aregiven below and/or in the claims.

The acid-functional monomer may be selected from the group consisting ofacrylic acid, methacrylic acid, itaconic anhydride, maleic anhydride,methylene malonic acid, itaconic acid, crotonic acid and fumaric acidand monobutyl itaconate.

The bio-renewable monomers may comprise bio-renewable (meth)acrylic acidand or bio-renewable alkyl(meth)acrylate (as well as optionally monomersof Formula 1).

The bio-renewable monomers may also comprise bio-renewable: α-methylenebutyrolactone, α-methylene valerolactone, α-methylene γ-R¹ butyrolactone(R¹ can be an optionally substituted alkyl or optionally substitutedaryl); itaconates such as dialkyl itaconates and monoalkyl itaconates,itaconic acid, itaconic anhydride, crotonic acid and alkyl estersthereof, citraconic acid and alkyl esters thereof, methylene malonicacid and its mono and dialkyl esters, citraconic anhydride, mesaconicacid and alkyl esters thereof.

Other suitable bio-renewable monomers may comprise bio-renewable: N—R²,α-methylene butyrolactam (R² can be an optionally substituted alkyl oroptionally substituted aryl); N—R², α-methylene γ-R¹ butyrolactam;N-alkyl itaconimids; itaconmonoamids; itacondiamids; ialkylitaconamides, mono alkyl itaconamides; furfuryl(meth)acrylate; and fattyacid functional (meth)acrylates.

Polymer C and/or polymer D may comprise at least about 1.5 dpm/gC ofcarbon-14.

The composition may additionally comprising a crosslinking agent, beingreactable with any crosslinking functional groups of the polymer Cand/or polymer D on subsequent drying of the coating composition toeffect covalent bond crosslinking. The functional groups for providingcrosslinking may be selected from the group consisting of epoxy,hydroxyl, ketone and aldehyde groups. The crosslinking agent may also beselected, depending on the crosslinking functionality in the polymer Cand in the polymer D, from the group consisting of a polyisocyanate,melamine, glycoluril, a polyamine, and a polyhydrazide.

The composition may comprise less than 2 wt-% of added surfactant byweight of monomers used to make vinyl polymer C and vinyl polymer D.

The composition may comprise volatile organic compounds (VOC) in anamount of less than 100 g/L, preferably be substantially free of VOC.

A film, polish, varnish, lacquer, paint, ink and/or adhesive maycomprise an aqueous coating composition of polymer C and polymer D andthese compositions may also be used as a protective coating on a wood,plastic, paper and/or metal substrate.

In a preferred embodiment of the invention the monomers α[alpha]) iii)and β[beta])iii) comprise individually at least 10 wt-%, more preferablyat least 20 wt-%, most preferably at least 30 wt-% and especiallypreferably at least 50 wt-%, based on the composition of monomersα[alpha]) iii) and β[beta])iii, of compounds of Formula 2 such as lowerdi-esters of itaconic acid (in addition to or replacing the higheritaconate diesters such as DBI). Although the concentration of itaconatemonomers in α[alpha]) iii) and β[beta])iii, can be similar, it ispreferred that the concentrations are different. In each of thepreferred cases described above, it is preferred that the concentrationof itaconate monomers in the other phase is 0 wt-%.

Preferably polymer C acts as a (co-)surfactant for the preparation ofpolymer D.

Preferably the concentration of olefinically unsaturated monomers usedto form polymer C are 10 to 65 wt-%, more preferably 15 to 60 wt-% andespecially 20 to 55 wt-% by weight of the monomers used to formpolymer(s) C and polymer(s) D.

Preferably the concentration of olefinically unsaturated monomers usedto form the polymer D are 90 to 35 wt-%, more preferably 85 to 40 wt-%and especially 80 to 45 wt-% by weight of the monomers used to formpolymer(s) C and polymer(s) D.

The monomer system used for the preparation of polymer C and polymer Dis any suitable combination of olefinically unsaturated monomers whichis amenable to copolymerisation (including the bio-renewable monomersdescribed herein which may of course also be acid-functional,crosslinkable etc as described herein).

Acid-functional olefinically unsaturated monomers (used in polymer Cpreferably in sufficient concentration to render the resulting polymersurface active) may be a monomer bearing an acid-forming group whichyields, or is subsequently convertible to, an acid-functional group(such as an anhydride, e.g. methacrylic anhydride or maleic anhydride)or an acid. Examples of such acid functional monomers have already beengiven as component (b) previously and may also be used in this aspect ofthe invention.

Typically polymer C comprises 1 to 45 wt-% of acid functional monomers,preferably 3 to 30 wt-% and more preferably 3 to 20 wt-%.

Polymer C may comprise polyethylene glycol(meth)acrylates or theirmethyl ether analogues that can render polymer C surface active. Whencopolymerising these monomers, a lower acid concentration can beapplied, for example polymer C may then comprise 1 to 10 wt-% of acidfunctional monomers.

Typically polymer D comprises less than 5 wt-% of any acid functionalmonomers and preferably less than 2 wt-%, and in some preferredembodiments none at all.

Polymer D may also comprise polyethylene glycol(meth)acrylates or theirmethyl ether analogues which may contribute to reducing the MFFT of theresulting composition.

Other, non-acid functional, non-crosslinking monomers which may becopolymerized with the acid monomers include acrylate and methacrylateesters and styrenes; also dienes such as 1,3-butadiene and isoprene,vinyl esters such as vinyl acetate, and vinyl alkanoates. Methacrylatesinclude normal or branched alkyl esters of C1 to C12 alcohols andmethacrylic acid, such as methyl methacrylate, ethyl methacrylate, andn-butyl methacrylate, and (usually C5 to C12) cycloalkyl methacrylates,such as isobornyl methacrylate and cyclohexyl methacrylate. Acrylatesinclude normal and branched alkyl esters of C1 to C12 alcohols andacrylic acid, such as methyl acrylate, ethyl acrylate, n-butyl acrylate,and 2-ethylhexyl acrylate, and (usually C5-C12) cycloalkyl acrylatessuch as isobornyl acrylate and cyclohexylacrylate. Also included are(meth)acrylamide, and mono- or di-alkyl amides of (meth)acrylic acid.Styrenics include styrene itself and the various substituted styrenes,such as alpha-methyl styrene and t-butyl styrene. Nitriles such asacrylonitrile and methacrylonitrile may also be polymerised, as well asolefinically unsaturated halides such as vinyl chloride, vinylidenechloride; vinyl fluoride. and (meth)acrylamide.

Typically polymer C comprises 98.5 to 50 wt-% of non acid functional,non-crosslinking monomers, preferably 96 to 65 wt-%, and more preferably96 to 75 wt-%.

Functional monomers which impart crosslinkability (crosslinking monomersfor short) include epoxy (usually glycidyl) and hydroxyalkyl (usuallyC1-C12, e.g. hydroxyethyl)methacrylates and acrylates, as well as ketoor aldehyde functional monomers such as acrolein, methacrolein and vinylmethyl ketone, the acetoacetoxy esters of hydroxyalkyl (usually C1-C12)acrylates and methacrylates such as acetoacetoxyethyl methacrylate andacrylate, and also keto-containing amides such as diacetone acrylamide.The purpose of using such functional monomer is to provide subsequentcrosslinkability in the resulting polymer system as discussed. (Inprinciple the functional monomer used for imparting crosslinkabilitycould be acid-bearing monomer, but this is not usual and therefore forthe purpose of this invention acid functional monomers are notconsidered as crosslinkable monomers although they may act as such.

Preferably, polymer C comprises 0.5 to 25 wt-%, more preferably 0.5 to25 wt-%, most preferably 1 to 15 wt-%, and especially 1 to 10 wt-% ofcrosslinking monomers.

Preferably polymer C has a weight average molecular weight (M_(w)) asdetermined with GPC of from 1500 to 100,000 g/mol, more preferably 2000to 50,000 g/mol and particularly 3,000 to 40,000 g/mol.

The weight average molecular weight (M_(w)) of polymer D as determinedwith GPC is preferably more than 100,000 g/mol, and most preferably morethan 150,000 g/mol. The upper limit does not usually exceed 5,000,000g/mol.

Preferably the weight average molecular weight (M_(w)) of polymer C islower than the weight average molecular weight (M_(w)) of polymer D, andmost preferably there is a molecular weight difference of at least30,000 g/mol, especially at least 50,000 g/mol, and typically at least100,000 g/mol.

Preferably the difference in Tg (expressed as degrees Celsius) betweenpolymer C and polymer D is at least 40 degrees and more preferably atleast 60 degrees.

In one embodiment of this aspect of the invention the Tg of polymer C ishigher than that of polymer D. In this embodiment the preferred Tg ofpolymer C is from 50 to 125° C. and particularly from 70 to 125° C. TheTg of polymer C should then be at least 20 degrees higher than, morepreferably at least 40 degrees higher than the Tg of polymer D (bothexpressed as degrees Celsius). Preferably the Tg of polymer D in thisembodiment is from −(minus) 50 to 40° C. and more preferably from−(minus) 30 to 30° C. and especially from −(minus) 20 to 30° C.

In another embodiment of the invention the Tg of polymer C is lower thanthat of polymer D. In this embodiment the preferred Tg of polymer C isless than 50° C. and more preferably is of from −(minus) 15 to 49° C.Preferably the Tg of polymer D in this embodiment is from 50 to 125° C.and particularly from 70 to 125° C.

Polymer C may be formed using a number of processes. These includeemulsion polymerisation, suspension polymerisation, bulk polymerisationand solution polymerisation. Such processes are extremely well known aredescribed elsewhere in this specification and need not be describedfurther in great detail.

In another embodiment polymer C is made via a bulk polymerisationprocess. Bulk polymerisation of olefinically unsaturated monomers isdescribed in detail in EP 0156170, WO 82/02387, and U.S. Pat. No.4,414,370.

In general in a bulk polymerisation process a mixture of two or moremonomers are charged continuously into a reactor zone containing moltenvinyl polymer having the same ratio of vinyl monomers as the monomermixture. The molten mixture is maintained at a preset temperature toprovide a vinyl polymer of the desired molecular weight. The product ispumped out of the reaction zone at the same rates as the monomers arecharged to the reaction zone to provide a fixed level of vinyl monomerand vinyl polymer in the system. The particular flow rate selected willdepend upon the reaction temperature, vinyl monomers, desired molecularweight and desired polydispersity.

The minimum reaction temperature will vary, depending on the particularmonomers charged to the reactor. In order to obtain a polymer C for usein the invention with the desired molecular weight the reactiontemperature is preferably maintained from about 135° C. to about 310°C., more preferably from about 150° C. to 275° C. A conventionalfree-radical-yielding initiator may be used and optionally a chaintransfer agent may be added to control the molecular weight.

Alternatively polymer C may be prepared by means of a suspension ormicro-suspension polymerisation process. In this process, monomer andwater are introduced into the polymerisation reactor and apolymerisation initiator, along with other chemical additives, are addedto initiate the polymerisation reaction. The contents of the reactionvessel are continually mixed to maintain the suspension and ensure auniform particle size of the resulting polymer.

Polymer C may also be made by a solution dispersion polymerisation orsolvent assisted dispersion polymerisation (SAD) process where thepolymerisation process can be carried out in the presence of an organicsolvent. Typical organic solvents which may be used include aromatichydrocarbons such as benzene toluene, and the xylenes, ethers such asdiethyl ether, tetrahydrofuran, alkoxylated ethylene glycol; alcoholssuch as methanol, ethanol, propanol, butanol and alcohols with at leastsix carbons, such as octanol. and their esters with carboxylic acidssuch as acetic, propionic and butyric acids, ketones such as acetone ormethyl ethyl ketone, and liquid tertiary amines such as pyridine.Mixtures of solvents may also be used. Typical solvents would certainlyinclude alkyl glycols, such as butyl glycol or dipropylene glycoldimethyl ether (Dowanol DMM) or dipropylene glycol methyl ether (DowanolDPM). An example of an aromatic solvent that is regularly used isSolvesso 100. Preferably bio-renewable solvents (for example asavailable from Liberty Chemicals) are used.

Often the reaction temperature is around 140° C. to 160° C. and can alsobe a carried out at an elevated pressure so that lower boiling pointsolvents can be used. An advantage of lower boiling point solvents isthat they can be more easily removed in order to make a low VOC aqueouscomposition.

Preferably the compositions of the invention have VOC levels of lessthan 100 g/L and more preferably less than 80 g/L, most preferably lessthan 50 g/L and especially less than 20 g/L of volatile organiccomponents such as coalescing solvents.

Once polymer C is prepared then polymer D is prepared in the presence ofpolymer C and an aqueous composition is prepared by inter aliasolubilising polymer C before during or after the preparation of polymerD. Polymer C can serve as an (co-)emulsifier for polymer D without whichpolymer D cannot be sufficiently dispersed in the aqueous composition ofthe invention. By (co-)emulsifier is meant that although polymer C actsas an emulsifier, additional emulsifiers may also be added.

Thus, polymer C contains a sufficient concentration of acidfunctionality or a high enough concentration of polyethyleneglycol(meth)acrylates to render the polymer partially or more preferablyfully soluble in aqueous media, if necessary by neutralization of acidgroups of the polymer, as would e.g. be achieved by adjustment of the pHof the aqueous medium. (If the acid-functional polymer C is onlypartially soluble in the aqueous medium of the emulsion, it will existtherein partly dispersed and partly dissolved). Usually, the medium inwhich the polymer C finds itself will be acidic (pH<7) and the acidgroups will be carboxyl groups so that dissolution and surface activitycan be affected by raising the pH of the medium (usually the aqueouspolymerisation medium in which the polymer C has been prepared) so as toneutralize the acid groups by the addition of a base, such as an organicor inorganic base, examples of which include organic amines such astrialkylamines (e.g. triethylamine, tributylamine), morpholine andalkanolamines, and inorganic bases such as ammonia, NaOH, KOH, and LiOH.Of course, the aqueous medium containing the acid functional polymer Amay already be alkaline (or sufficiently alkaline) such that the acidgroups (such as carboxyl groups) become neutralized without therequirement for positively adding a base to raise pH, or the acid groupsmay be or include very strong acid groups such as sulphonic acid groups(pKa 1 to 2) so that neutralization may not be necessary to achievedissolution. Further still, it is possible for acid monomers to bepolymerised in salt form rather than as the free acid.

The solubilization of the polymer C is preferably effected beforecarrying out the polymerisation of step b′) as preferably this producesa product having an improved balance of MFFT and Koenig hardness.

Polymer C is present during the polymerisation process to make polymerD. Polymer D may be formed using a number of processes. These includeemulsion polymerisation, bulk polymerisation and solutionpolymerisation.

A preferred feature of this aspect of the invention is that it is oftenpossible to eliminate or much reduce the requirement for the addition ofa surfactant to act as an emulsifier to make polymer D because polymer Citself can fulfil such a function (i.e. act as an emulsifying agent).Thus the aqueous composition of the invention preferably contains a verylow level of such added emulsifier (not counting polymer C itself), withusually less than 0.5% (preferably less than 0.25%, and often zero)based on the total wt of monomers charged being used, and with the onlysurfactant present preferably being that remaining from polymer Cpolymerisation (not counting the polymer C itself). In fact the overalllevel of surfactant (not counting the polymer C itself) is preferably<1% more preferably <0.5%, particularly <0.35%, based on the total wt ofmonomers charged for polymer D.

The polymerisation to make polymer D could be carried out using a chaintransfer agent, but (unlike in the preparation of polymer C) is usuallyeffected without the use of such a material in order to ensure a highermolecular weight.

Polymer D may be considered as a hydrophobic polymer, this type ofpolymer being well understood by those skilled in the art. Generallyspeaking it may be considered herein as a water-insoluble polymer whosewater-insolubility is maintained throughout the pH range. Thehydrophobic nature of the polymer is achieved by virtue of the polymercontaining a sufficient concentration of at least one hydrophobicmonomer (i.e. in polymerised form) to render the polymer hydrophobic andwater-insoluble throughout the pH range.

Polymer D may also comprises 0.5 to 25 wt-%, more preferably 0.5 to 20wt-%, most preferably 1 to 12 wt-%, especially 1 to 8 wt-%, for example1 to 5 wt-% of crosslinking multifunctional (meth)acrylate monomer(s).In general it will be appreciated that given the respective natures ofpolymers C and D for a given system the amount of multifunctional(meth)acrylate crosslinking monomer used in polymer C is more likely tobe less than the amount used in polymer D.

It will be appreciated that polymer C and optionally polymer D possessfunctional groups for imparting latent crosslinkability to thecomposition (i.e. so that crosslinking takes place e.g. after theformation of a coating there from) when combined with the crosslinkingagent (as described elsewhere herein).

If crosslinking monomers are present then preferably the amount ofcrosslinking agent that is employed is such that the ratio of the numberof crosslinker groups present in the polymer C and (if employed) in thepolymer D to the number of reactive groups (for crosslinking purposes)in the crosslinking agent is within the range of from 10/1 to 1/3,preferably 2/1 to 1/1.5.

Polymers of this aspect of the invention may also be iminated asdescribed elsewhere herein.

The crosslinker is usually combined with the aqueous composition byadding it thereto after the preparation of polymer D (and sometimes justbefore use of the composition), although it may in principle also becombined by performing the polymerisation of polymer D in the presenceof the crosslinking agent. A combination of both incorporationexpedients may also in principle be used.

According to an embodiment of the invention there is provided an aqueouspolymer coating composition comprising at least:

α(alpha)) a vinyl polymer C, comprising:

-   -   i) 4 to 25 wt-% of acid-functional olefinically unsaturated        monomers;    -   ii) 0 to 15 wt-% of crosslinking unsaturated monomers; and    -   iii) 96 to 60 wt-% of non-acid functional, non-crosslinking        olefinically unsaturated monomers; said polymer C being obtained        by an emulsion polymerisation process and having a molecular        weight within the range of from 3,000 to 65,000 g/mol, a Tg of        at least 50° C. and an acid value>20 mgKOH/g; and        β(beta)) a vinyl polymer D, made in the presence of neutralised        polymer C and comprising:    -   i) 0 to 4 wt-%, more preferably 0 wt-% of acid-functional        olefinically unsaturated monomers;    -   ii) 0 to 12 wt-%, more preferably 1 to 8 wt-% of        crosslinking-functional olefinically unsaturated monomers; and    -   iii) 100 to 84 wt-% of non-acid functional, non-crosslinking        olefinically unsaturated monomers;        wherein polymer D has a molecular weight of at least 80,000        g/mol and a Tg less than 50° C.; and        where the wt-% of polymer C is 10 to 60, more preferred 20 to 50        wt-% based on the weight of polymer C and polymer D together;        and        where polymer(s) C and polymer(s) D combined contain at least 30        wt-% of itaconate diester monomer according to Formula 1.

The wt-% of olefinically unsaturated monomers used to form polymer C arein the range of from 10 to 60, more preferably 20 to 50 wt-% based onthe weight of olefinically unsaturated monomers used to form polymer Cand polymer D together.

According to an embodiment of the invention there is provided a processfor the production of the aqueous polymer coating composition, whichprocess comprises steps:

-   -   1) a first polymerisation step, to form polymer C;    -   2) a second polymerisation step in the presence of the resulting        polymer C from step 1) to form polymer D;    -   3) a neutralisation step before/after or during step 2) to        solubilise polymer D;    -   4) the optional step of iminating (part of) the acid groups        using alkylene imine    -   5) the optional addition of a crosslinking agent after the        polymerisation step a) and/or step 2), said crosslinking agent        being reactable with any crosslinking functional groups of the        polymer C and/or polymer D on subsequent drying of the coating        composition to effect covalent bond crosslinking.

In a preferred embodiment the acid functional monomer in polymer C isselected from acrylic acid; methacrylic acid, crotonic acid, itaconicanhydride and itaconic acid; the crosslinking functional monomer used inboth polymer C and polymer D is diacetone acrylamide and the crosslinkeris adipic acid dihydrazide.

According to another embodiment of the invention there is provided aprocess for the production of the aqueous polymer coating composition,which process comprises steps:

-   -   1) where vinyl polymer C is made by an emulsion polymerisation        process,    -   2) a subsequent neutralisation step; and    -   3) where subsequently polymer D is made by polymerisation in the        presence of polymer C;        wherein both vinyl polymer C and vinyl polymer D comprise at        least one carbonyl functional olefinically unsaturated monomer;        wherein the acid value of vinyl polymer C is between 30 and 110        mgKOH/g and the acid value of vinyl polymer D is below 10        mgKOH/g, more preferred below 5 mgKOH/g; and wherein the        crosslinker is an aliphatic dihydrazide.

According to yet another embodiment of the invention there is provided aprocess for the production of the aqueous polymer coating composition,which process comprises steps:

-   -   1) where polymer C is made by a bulk polymerisation process and        more preferably a continuous bulk polymerisation process,    -   2) where polymer C is dissipated in water and (partially)        neutralised, preferably with an organic amine or NaOH, KOH or        LiOH; and    -   3) where subsequently polymer D is made by polymerisation in an        aqueous medium in the presence of the neutralised polymer C;        wherein the acid value of vinyl polymer C is between 40 and 300        mgKOH/g of solid polymer;        wherein polymer C has a Tg of at least 70° C. and more        preferably at least 90° C.; and        wherein polymer C has a molecular weight in the range of from        2,000 to 25,000 g/mol.

According to yet a further embodiment of the invention there is provideda process for the production of the aqueous polymer coating composition,which process comprises steps:

-   -   1) where polymer C is made by solution polymerisation,        preferably in a solvent selected from the group consisting of        acetone, methyl ethylketone, ethanol, iso-propanol or mixtures        thereof;    -   2) a subsequent neutralisation step comprising neutralising at        least part of the acid groups with a base (preferably an organic        amine), adding water and emulsifying polymer C    -   3) where subsequently polymer D is made by emulsion        polymerisation in the presence of polymer C;    -   4) where the solvent is removed by evaporation;        wherein polymer C has a Tg of at least 50° C.,        wherein polymer D has a Tg of no more than 50° C., and        wherein polymer c and polymer D have a glass transition        temperature difference of at least 25° C.

In yet another embodiment there is provided an aqueous copolymercomposition according to this aspect of the invention wherein polymer Dcontains between 0.1 and 1.5 wt-% of a multi unsaturated monomer,preferably divinyl benzene.

It is preferred that most of the higher itaconate ester present in thecomposition is used to prepare polymer D rather than polymer C.Therefore in yet still another embodiment there is provided an aqueouscopolymer composition according to this aspect of the invention whereinpolymer D contains at least 50 wt-%, more preferably at least 75 wt-%,of all itaconate monomer according to Formula 1 present in the totalcopolymer composition, and polymer C contains no more than 50 wt-%, morepreferably not more than 25 wt-% of all itaconate monomer according toFormula 1 present in the total copolymer composition.

Preferably the average particle size of the aqueous composition of theinvention is between 70 and 140 nm.

The solids content of an aqueous composition of the invention is usuallywithin the range of from about 20 to 65 wt-% on a total weight basis,more usually 30 to 55 wt-%. Solids content can, if desired, be adjustedby adding water or removing water (e.g. by distillation orultrafiltration).

A still yet another aspect of the invention is described as followsincluding the specific additional and/or sub-problems it is designed toaddress.

The present invention relates to vinyl polymer beads comprising at least20 wt-% (preferably at least 30 wt-%) of a monomer of Formula 1(usefully DBI) preferably from a bio-renewable source and to such vinylpolymer beads as well as a process for making them and their use incoatings, inks and adhesives.

Vinyl polymers which are prepared with emulsion polymerisationtechnology allow a good control over critical polymer parameters likemolecular weight, particle size in the nm (nanometer) range (typically50-300 nm) and residual monomer content. However, few micron-sizedparticles are obtained during emulsion polymerisation. Due to the smallparticle size dried emulsion vinyl polymers have a much larger dustingtendency compared to dried vinyl polymer beads obtainable by suspensionpolymerization. On the other hand polymer emulsions used as such toavoid the dusting issue need to be preserved to prevent bacterial orfungal growth.

The problem of dustiness of dried emulsion polymers can be overcome bybead-type suspension polymerisation which is a well known method ofpolymerisation in which the polymer formed is obtained as micron sizedspherical beads or pearls. Even though the water soluble by-products maybe removed with the stationary water phase during the final de-wateringand washing cycle the water insoluble by-products such as in particularthe unreacted monomers stay within the polymer beads and lead tocharacteristic off odours, lowered glass transition temperatures (T_(g))and toxicological issues, especially when the monomers are taken fromvinyl acid/methyl vinyl acid and their esters.

An object of this aspect of the present invention is to solve some orall of the problems or disadvantages (such as identified herein) withthe prior art.

By the term “polymer beads” in connection with the present invention ismeant polymer particles that are simple to isolate e.g. by filtering orcentrifuging. The polymer beads in connection with the present inventionare micron-sized, for example. typically have an average diameter of atleast 50 μm (micron), preferably at least 150 μm (micron). Generally,the beads have an average diameter between 50 and 1500 μm (micron), andmore preferably between 150 to 600 μm (micron).

As used herein the term ‘micron sized’ denotes an object that has atleast one linear dimension having a mean size between about 0.1 μm (1μm=one micron=1×10⁻⁶ m) to about 2000 μm. A preferred mean size for themicron-sized materials described herein is less than about 1000 μm(micron), more preferably less than about 600 μm (micron) mostpreferably less than about 500 μm (micron), for example less that about200 μm (micron). Micron-sized materials exist with the micron-size inthree dimensions (micro-particles), two dimensions (micro-tubes having amicro-sized cross section, but indeterminate length) or one dimension(micro-layers having a micro-sized thickness, but indeterminate area).Usefully the present invention relates to materials that comprisemicro-particles. The particle size values given herein may be measuredby a Coulter LS230 Particle Size Analyser (laser diffraction) and arethe volume mean. The particle sizes are quoted as a linear dimensionwhich would be the diameter of an approximate spherical particle havingthe same volume as the volume mean measured.

Such vinyl polymer beads are widely applied in the field of coatings(e.g. road markings, marine coatings), adhesives, colorants,photographic applications, inks, powder coatings or plastics filler andeven in personal care products if the residual monomer content is lowenough. The beads may be used in a liquid medium which may be aqueous orsolvent based. Preferably if a solvent is used, a bio-renewable solventis used. Bio-renewable solvents include for example bio-alcohols,xylene, butyl acetate, ethyl acetate, ethyl lactate and the VertecBio™solvents available from Liberty Chemicals.

The preparation of vinyl polymer beads is well known and is described infor example EP739359 which discloses the use of a cobalt chelate for Mwcontrol and in U.S. Pat. No. 4,463,032 which discloses polymers in beadform which are conventionally produced by a bead (suspension)polymerisation method where with this method, the monomers (dispersephase) are dispersed in a non-solvent (continuous phase) by mechanicalaction (agitation) and polymerised in that form.

Thus, this aspect of the invention provides a process for preparingvinyl polymer beads having a molecular weight in the range of from 3,000to 500,000 g/mol and a glass transition temperature in the range of from30° C. to 175° C. and an acid value less than 150 mgKOH/g, preferablyfrom 0 to 100 mgKOH/g; said process comprising aqueous suspensionpolymerisation of olefinically unsaturated monomers using a free-radicalinitiator, wherein at least 20 wt-% of the olefinically unsaturatedmonomers used comprises at least one monomer of Formula 1 (preferablydi(n-butyl) itaconate (DBI), more preferably derived from abio-renewable source.

The monomers of Formula 1 correspond to the component (a) of the processof present invention, and any acid functional monomers used to achievethe desired AV correspond to component (b) of the present invention; andthe remaining monomers that may be used correspond as appropriate tooptional components (c) and/or (d) of the process of the presentinvention.

Other preferred features of this aspect of the present invention aregiven below and/or in the claims.

A process for preparing vinyl polymer beads as described herein wherethe olefinically unsaturated monomers are biorenewable and also compriseat least one monomer are selected from the group consistingbio-renewable (meth)acrylic acid and or bio-renewablealkyl(meth)acrylate.

Preferred bio-renewable monomers are selected from the group consistingof bio-renewable: α-methylene butyrolactone, α-methylene valerolactone,α-methylene γ-R¹ butyrolactone (R¹ can be an optionally substitutedalkyl or optionally substituted aryl); itaconates such as dialkylitaconates and monoalkyl itaconates, itaconic acid, itaconic anhydride,crotonic acid and alkyl esters thereof, citraconic acid and alkyl estersthereof, maleic anhydride, methylene malonic acid and its mono anddialkyl esters, citraconic anhydride, mesaconic acid and alkyl estersthereof.

More preferred bio-renewable monomers are selected from the groupconsisting of bio-renewable: N—R², α-methylene butyrolactam (R² can bean optionally substituted alkyl or optionally substituted aryl); N—R²,α-methylene γ-R¹ butyrolactam; N-alkyl itaconimids; itaconmonoamids;itacondiamids; ialkyl itaconamides, mono alkyl itaconamides;furfuryl(meth)acrylate; and fatty acid functional (meth)acrylates.

The above process may further comprise the isolation of the beadsfollowed by a drying step at 40 to 100 C optionally carried out over aperiod of 3 to 40 hours.

Vinyl polymer beads obtained and/or obtainable by this process forms afurther aspect of the invention.

The vinyl polymer beads of the invention and/or the copolymers thatcomprise them may additionally have one or more of the followingpreferred properties: comprise at least about 1.5 dpm/gC of carbon-14.

have an acid value (AV) from 0 to 20 mgKOH/g, more preferably either inon embodiment from 45 to 65 mg KOH/g, or an alternative embodiment from100 to 150 mg KOH/g.

A still yet other aspect of the invention provides a compositioncomprising the vinyl polymer beads of the invention and a carrier.

A another aspect of the invention provides a method of coating a surfaceof a substrate with a composition comprising vinyl beads comprising thesteps of applying the composition to the surface and then drying thecomposition. Suitable substrate may be selected from the groupconsisting of tarmac, wood, plastic, metal and paper.

Compositions comprising the vinyl polymer beads of the invention may beused as a bio-renewable liquid medium in a coating composition.

The respective ratio of the weight of dispersed phase to the weight ofthe continuous phase may be from 10/90 to 50/50 and more preferably from30/70 to 45/55.

In another embodiment, the invention relates to vinyl polymer beadsobtainable by the process according to this aspect of the invention. Inparticular the vinyl polymer beads according to the invention have aresidual monomer content of less than 2500 ppm and more preferably lessthan 1000 ppm.

The vinyl polymer beads according to the invention are prepared bysuspension polymerisation (also known as granular, bead, or pearlpolymerisation due to the shape of the resultant polymer particles)according to known methods in the art as illustrated in the examples.

Initiators for polymerizing the monomers to provide the vinyl polymerbeads of the invention are those which are normally suitable forfree-radical polymerisation of acrylate monomers and which areoil-soluble and have low solubility in water such as e.g. organicperoxides, organic peroxyesters and organic azo initiators. Theinitiator is generally used in an amount of about 0.1 to 2 wt-% based onthe total monomer content.

Useful chain transfer agents include mercapto-acids and alkyl estersthereof, carbon tetrabromide, mixtures thereof and cobalt chelate.Dodecylmercaptane is preferred. The mercapto chain transfer agentgenerally is used in an amount of about 0.01 to 3.0 wt-%, preferably inan amount of 0.1 to 2 wt-% based on the total monomer content. Typicalcobalt chelate levels used range from 1 to 200 ppm and more preferablyfrom 10 to 100 ppm.

Optionally, a water soluble inhibitor can be added to inhibitpolymerisation in the water phase in order to prevent the formation oftoo much polymer by emulsion and/or solution polymerisation in the waterphase, which can result in bead agglomeration or emulsion typepolymerization. Suitable inhibitors include those selected fromthiosulfates, thiocyanates, water soluble hydroquinones and nitrites.When used, the water soluble inhibitor can generally be added in anamount of from about 0.01 to about 1 parts by weight based on 100 partstotal monomer content.

Furthermore, a water soluble or water dispersible polymeric stabiliseris needed to stabilize the suspension and in order to obtain stablebeads. The stabiliser is preferably a synthetic water soluble or waterdispersible polymer such as e.g. polyvinylalcohol, gelatine, starch,methylcellulose, carboxymethylcellulose, hydroxyethylcellulose,poly(meth)vinyl acid and their sodium salts, and the like. Thestabiliser is preferably used in an amount of about 0.001 to 10 wt-%,more preferably in an amount of about 0.01 to 1 wt-% based on the totalmonomer content.

Other additives can optionally be used such as e.g. mono-, di- andtrivalent metal salts, borax, urea, glyoxal and urea formaldehyde resin.Biocides (both bactericides and fungicides) can also be added, in orderto prevent microbial growth in the finished product and during its usein water based systems.

The monomers, free-radical initiator, and any optional materials can bemixed together in the prescribed ratio to form a premix. The stabilisercan be combined with water and then with the premix to form an oil inwater suspension. The resulting suspension typically comprises fromabout 10 to about 50 weight percent monomer premix and from about 90 toabout 50 weight percent water phase. Bead-type suspension polymerisationin accordance with the present invention is typically a thermallyinitiated polymerisation and is preferably carried out with agitationfor about 2 to about 16 hours at a temperature between about 40° C. and90° C.

After isolation of the beads according to standard methods such asfiltration or centrifugation the beads are preferably subjected to anextended drying, preferably at about 40 to 100° C. depending on theactual Tg of the final polymer composition. The drying can be performedby commonly known means to a person skilled in the art such as e.g.using a fluidised bed dryer or a conventional oven. The drying time canbe easily adjusted by a person skilled in the art and is usually carriedout over a period of from about 3 to about 40 hours, more usually from 8to 20 hours and in particular from 8 to 10 hours.

In a preferred embodiment the process further comprises the isolation ofthe vinyl polymer beads followed by the step of drying at a temperatureof from 40 to 100° C. and more preferably from 80 to 100° C.

In addition to the monomers of Formula 1 (such as higher itaconateesters e.g. DBI), other monomers that may be used to prepare copolymersof the invention comprise:

unsaturated monomers belonging to the general class of methacrylates,e.g. C₁₋₃₀alkyl irrespective of the functionality;

unsaturated monomers belonging to the general class of acrylates, e.g.C₁₋₃₀alkyl irrespective of the functionality;

unsaturated hydrocarbon monomers like e.g. butadiene, isoprene, styrene,vinyl toluene, α-methyl styrene, tert.-butyl styrene etc.;

unsaturated monomers belonging to the class of vinyl halides, vinylesters, vinyl ethers; multi-olefinically unsaturated monomers such asdi-allylphthalate, allylmethacrylate; and/or

any multi unsaturated monomers of any of the aforementioned types.

Preferably the monomers that are other than of Formula 1 are alsoderived from a bio-renewable source.

Improved properties of beads of the present invention may include heatresistance, colloidal stability, pigment compatibility, surfaceactivity, blocking resistance and reduced MFFT depending on the monomersused.

The monomer system used for the preparation of the vinyl polymer beadsmay comprise in addition to those of Formula 1 any suitable combinationof olefinically unsaturated monomers which is amenable tocopolymerisation (including the bio-renewable monomers described hereinwhich may of course also be acid-functional, crosslinkable etc atdescribed below).

Acid-functional olefinically unsaturated monomers include a monomerbearing an acid-forming group which yields, or is subsequentlyconvertible to, such an acid-functional group (such as an anhydride,e.g. methacrylic anhydride or maleic anhydride). Examples of such acidfunctional monomers have already been given as component (b) previouslyand may also be used in this aspect of the invention.

Other, non-acid functional, non-crosslinking monomers which may becopolymerised with the acid monomers include acrylate and methacrylateesters and styrenes; also dienes such as 1,3-butadiene and isoprene,vinyl esters such as vinyl acetate, and vinyl alkanoates. Methacrylatesinclude normal or branched alkyl esters of C1 to C12 alcohols andmethacrylic acid, such as methyl methacrylate, ethyl methacrylate, andn-butyl methacrylate, and (usually C5 to C12) cycloalkyl methacrylatesacid such as isobornyl methacrylate and cyclohexyl methacrylate.Acrylates include normal and branched alkyl esters of C1 to C12 alcoholsand acrylic acid, such as methyl acrylate, ethyl acrylate, n-butylacrylate, and 2-ethylhexyl acrylate, and (usually C5-C12) cycloalkylacrylates such as isobornyl acrylate and cyclohexylacrylate. Styrenesinclude styrene itself and the various substituted styrenes, such as.alpha.-methyl styrene and t-butyl styrene. Nitriles such asacrylonitrile and methacrylonitrile may also be polymerised, as well asolefinically unsaturated halides such as vinyl chloride, vinylidenechloride and vinyl fluoride.

Functional monomers which impart crosslinkability (crosslinking monomersfor short) include epoxy (usually glycidyl) and hydroxyalkyl (usuallyC1-C12, e.g. hydroxyethyl)methacrylates and acrylates, as well as ketoor aldehyde functional monomers such as acrolein, methacrolein and vinylmethyl ketone, the acetoacetoxy esters of hydroxyalkyl (usually C1-C12)acrylates and methacrylates such as acetoacetoxyethyl methacrylate andacrylate, and also keto-containing amides such as diacetone acrylamide.The purpose of using such functional monomer is to provide subsequentcrosslinkability in the resulting polymer system as discussed. (Inprinciple the functional monomer used for imparting crosslinkabilitycould be acid-bearing monomer, but this is not usual) and for thepurpose of this invention acid-bearing monomers are not considered ascrosslinking monomers.

In an especially preferred embodiment of the invention is provided avinyl copolymer prepared via suspension polymerization comprising atleast 10 wt-% on total copolymer composition of mono- or diesters ofitaconic acid (in addition to the DBI). More preferably the totalcontent of mono- or diesters of itaconic acid (including the DBI) is atleast 20 wt-%, more preferably 25 wt-%, even more preferably at least 30wt-%, most preferably at least 40 wt-%, and especially preferably atleast 50 wt-%.

The vinyl polymer beads made according to the present inventionpreferably have a molecular weight in the range of from preferably 5,000to 100,000 g/mol.

The vinyl polymer beads made according to the present inventionpreferably have a glass transition temperature in the range of from 35°C. to 150° C. and more preferably in the range of from 50° C. to 115° C.

The vinyl polymer beads made according to the present inventionpreferably have a an average particle size of about 50 to 500 μm(micron) more preferably from 200 to 500 μm (micron).

The vinyl polymer beads made according to the present invention in oneembodiment preferably have an acid value of from 0 to 20 mgKOH/g.

The vinyl polymer beads of the invention may be used in coatingcompositions but also in printing compositions and/or personal carecompositions

The vinyl polymer beads made according to the present invention inanother embodiment preferably have an acid value of from 45 to 65mgKOH/g when used for printing compositions.

The vinyl polymer beads made according to the present invention inanother embodiment preferably have an acid value of from 100 to 150mgKOH/g when used for personal care compositions.

The term “activated unsaturated moiety”, is used herein to denote aspecies comprising at least one unsaturated carbon to carbon double bondin chemical proximity to at least one activating moiety. Preferably theactivating moiety comprises any group which activates an ethylenicallyunsaturated double bond for addition thereon by a suitable electrophilicgroup. Conveniently the activating moiety comprises oxy, thio,(optionally organo substituted)amino, thiocarbonyl and/or carbonylgroups (the latter two groups optionally substituted by thio, oxy or(optionally organo substituted) amino). More convenient activatingmoieties are (thio)ether, (thio)ester and/or (thio)amide moiet(ies).Most convenient “activated unsaturated moieties” comprise an“unsaturated ester moiety” which denotes an organo species comprisingone or more “hydrocarbylidenyl(thio)carbonyl(thio)oxy” and/or one ormore “hydrocarbylidenyl(thio)-carbonyl(organo)amino” groups and/oranalogous and/or derived moieties for example moieties comprising(meth)acrylate functionalities and/or derivatives thereof. “Unsaturatedester moieties” may optionally comprise optionally substituted genericα,β-unsaturated acids, esters and/or other derivatives thereof includingthio derivatives and analogs thereof.

Preferred activated unsaturated moieties are those represented by aradical of Formula 4.

where n′ is 0 or 1, X⁶ is oxy or, thio; X⁷ is oxy, thio or NR¹⁷ (whereR¹⁷ represents H or optionally substituted organo), R¹³, R¹⁴, R¹⁵ andR¹⁶ each independently represent a bond to another moiety in Formula 1,H, optional substituent and/or optionally substituted organo groups,where optionally any of R¹³, R¹⁴, R¹⁵ and R¹⁶ may be linked to form aring; where at least one of R¹³, R¹⁴, R¹⁵ and R¹⁶ is a bond; and allsuitable isomers thereof, combinations thereof on the same speciesand/or mixtures thereof.

The terms “activated unsaturated moiety”; “unsaturated ester moiety”and/or Formula 4 herein represents part of a formula herein and as usedherein these terms denote a radical moiety which depending where themoiety is located in the formula may be monovalent or multivalent (e.g.divalent).

More preferred moieties of Formula 4 (including isomers and mixturesthereof) are those where n′ is 1; X⁶ is O; X⁷ is O, S or NR⁷.

R¹³, R¹⁴, R¹⁵ and R¹⁶ are independently selected from: a bond, H,optional substituents and optionally substituted C₁₋₁₀hydrocarbo,optionally R¹⁵ and R¹⁶ may be linked to form (together with the moietiesto which they are attached) a ring; and where present R¹⁷ is selectedfrom H and optionally substituted C₁₋₁₀hydrocarbo.

Most preferably n′ is 1, X⁶ is O; X⁷ is O or S and R¹³, R¹⁴, R¹⁵ and R¹⁶are independently a bond, H, hydroxy and/or optionally substitutedC₁₋₆hydrocarbyl.

For example n′ is 1, X⁶ and X⁷ are both O; and R³, R⁴, R⁵ and R⁶ areindependently a bond, H, OH, and/or C₁₋₄alkyl; or optionally R⁵ and R⁶may together form a divalent C₀₋₄alkylenecarbonylC₀₋₄alkylene moiety soFormula 4 represents a cyclic anhydride (e.g. when R¹⁵ and R¹⁶ togetherare carbonyl then Formula 4 represents a maleic anhydride or derivativethereof).

For moieties of Formula 4 where n′ is 1 and X⁶ and X⁷ are both O thenwhen one of (R¹³ and R¹⁴) is H and also R¹³ is H, Formula 4 representsan acrylate moiety, which includes acrylates (when both R¹³ and R¹⁴ areH) and derivatives thereof (when either R¹³ and R¹⁴ is not H). Similarlywhen one of (R¹³ and R¹⁴) is H and also R¹⁵ is CH₃, Formula 4 representsan methacrylate moiety, which includes methacrylates (when both R¹³ andR¹⁴ are H) and derivatives thereof (when either R¹³ and R¹⁴ is not H).Acrylate and/or methacrylate moieties of Formula 5 are particularlypreferred.

Conveniently moieties of Formula 4 are those where n′ is 1; X⁶ and X⁷are both O; R¹³ and R¹⁴ are independently a bond, H, CH₃ or OH, and R¹⁵is H or CH₃; R¹⁶ is H or R¹⁵ and R¹⁶ together are a divalent C═O group.

More conveniently moieties of Formula 4 are those where n′ is 1; X⁶ andX⁷ are both O; R¹³ is OH, R⁴ is CH₃, and R¹⁵ is H and R⁶ is a bondand/or tautomer(s) thereof (for example of an acetoacetoxy functionalspecies).

Most convenient unsaturated ester moieties are selected from:—OCO—CH═CH₂; —OCO—C(CH₃)═CH₂; acetoacetoxy, —OCOCH═C(CH₃)(OH) and allsuitable tautomer(s) thereof.

It will be appreciated that any suitable moieties represented by Formula4 could be used in the context of this invention such as other reactivemoieties.

Vinyl Polymer

Whilst the term vinyl polymer is commonly used to refer to thermoplasticpolymers derived by polymerization from compounds containing the vinylgroup (CH₂═CH—), the term “vinyl polymer” is used herein more broadly todenote any polymer (whether thermoplastic or not) that comprises (e.g.as repeat units therein) and/or is derived from monomers and/or polymerprecursors comprising one or more of the following moieties: activatedunsaturated moieties (such as acrylates and/or methacrylates); anyolefinically unsaturated moieties (such as vinyl moieties); mixturesthereof; and/or combinations thereof within the same moiety.

There is an increasing demand to use bio-renewable monomers in order toimprove the sustainability of the polymers used in for example coatingapplications. In view of concerns about depletion of fossil fuelresources or an increase in carbon dioxide in the air that poses aglobal-scale environmental problem in recent years, methods forproducing raw materials of these polymers from biomass resources haveattracted al lot of attention. Since these resources are renewable andtherefore have a carbon-neutral biomass, such methods are expected togain in particular importance in future. It is therefore a preferredfeature of the present invention and the aspects described herein thatwhere possible the monomers (especially the higher itaconate diesterssuch as DBI) as far as possible are biorenewable.

Preferably at least 30 wt-%, more preferably at least 50 wt-%, andespecially 70 wt-% of the olefinically unsaturated monomers used to formthe polymers of the invention are derived from at least onebio-renewable olefinically unsaturated monomer. Bio-renewable monomersmay be obtained fully or in part from bio-renewable sources. Thus it ispreferred to also measure the carbon-14 content to determine thebiorenewability.

The content of carbon-14 (C-14) is indicative of the age of a bio-basedmaterial. It is known in the art that C-14, which has a half life ofabout 5,700 years, is found in bio-renewable materials but not in fossilfuels. Thus, “bio-renewable materials” refer to organic materials inwhich the carbon comes from non-fossil biological sources. Examples ofbio-renewable materials include, but are not limited to, sugars,starches, corns, natural fibres, sugarcanes, beets, citrus fruits, woodyplants, cellulosics, lignocelluosics, hemicelluloses, potatoes, plantoils, other polysaccharides such as pectin, chitin, levan, and pullulan,and a combination thereof.

C-14 levels can be determined by measuring its decay process(disintegrations per minute per gram carbon or dpm/gC) through liquidscintillation counting. In one embodiment of the present invention,polymer A, polymer B and/or the olefinically unsaturated monomer(s) thatare used to obtain polymer A and/or polymer B may consideredsufficiently biorenewable for the purposes of this embodiment of theinvention when the respective polymer A, polymer B and/or olefinicallyunsaturated monomer comprise an amount of carbon-14 to produce a decayof at least about 1.5 dpm/gC (disintegrations per minute per gramcarbon), more preferably at least 2 dpm/gC, most preferably at least 2.5dpm/gC, and especially at least 4 dpm/gC.

It is preferred that the higher itaconate diesters such as DBI arebiorenewable, however other monomers used in the present invention mayalso be biorenewable. Examples of bio-renewable monomers include but arenot limited to bio-based acrylics obtained by for example usingbio-derived alcohols such as bio-butanol and include (meth)acrylic acidand alkyl(meth)acrylate, where alkyl is preferably selected from methyl,ethyl, butyl or 2-ethylhexyl.

Acrylic acid can be made from glycerol, as is disclosed by Arkema, orfrom lactic acid as described by U.S. Pat. No. 7,687,661. Methacrylicacid can be prepared from ethene, methanol and carbon monoxide (allbio-renewable), as disclosed by Lucite International Ltd.

Olefinically unsaturated bio-renewable monomers which may additionallyprovide a contribution to improved coating properties includeα-methylene butyrolactone, α-methylene valerolactone, α-methylene γ-R³butyrolactone (R³ can be an optionally substituted alkyl or optionallysubstituted aryl); itaconates such as dialkyl itaconates (including DBI)and monoalkyl itaconates, itaconic acid, itaconic anhydride, crotonicacid and alkyl esters thereof, citraconic acid and alkyl esters thereof,methylene malonic acid and its mono and dialkyl esters, citraconicanhydride, mesaconic acid and alkyl esters thereof.

Other non-acid functional, non-crosslinking monomers include diesters ofitaconic acid. Preferred examples of such monomers include dimethylitaconate, diethyl itaconate, di-n-propyl itaconate, di-i-propylitaconate, di-n-butyl itaconate, di-i-butyl itaconate, and di-2-ethylhexyl itaconate.

Another useful set of useful bio-renewable monomers include N—R²,α-methylene butyrolactam (R² can be an optionally substituted alkyl oroptionally substituted aryl); N—R², α-methylene γ-R¹ butyrolactam;N-alkyl itaconimids; itaconmonoamids; itacondiamids; ialkylitaconamides, mono alkyl itaconamides; furfuryl(meth)acrylate; fattyacid functional (meth)acrylates such as DAPRO FX-522 from Elementis andVisiomer® MUMA from Evonik.

It is appreciated that certain features of the invention, which are forclarity described in the context of separate embodiments may also beprovided in combination in a single embodiment. Conversely variousfeatures of the invention, which are for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable sub-combination.

The object of the present invention is to solve some or all of theproblems or disadvantages (such as identified throughout the applicationherein) with the prior art.

Unless the context clearly indicates otherwise, as used herein pluralforms of the terms herein are to be construed as including the singularform and vice versa.

The term “comprising” as used herein will be understood to mean that thelist following is non exhaustive and may or may not include any otheradditional suitable items, for example one or more further feature(s),component(s), ingredient(s) and/or substituent(s) as appropriate.

The terms ‘effective’, ‘acceptable’ ‘active’ and/or ‘suitable’ (forexample with reference to any process, use, method, application,preparation, product, material, formulation, compound, monomer,oligomer, polymer precursor, and/or polymers described herein asappropriate) will be understood to refer to those features of theinvention which if used in the correct manner provide the requiredproperties to that which they are added and/or incorporated to be ofutility as described herein. Such utility may be direct for examplewhere a material has the required properties for the aforementioned usesand/or indirect for example where a material has use as a syntheticintermediate and/or diagnostic tool in preparing other materials ofdirect utility. As used herein these terms also denote that a functionalgroup is compatible with producing effective, acceptable, active and/orsuitable end products.

Preferred utility of the present invention comprises as a coatingcomposition.

In the discussion of the invention herein, unless stated to thecontrary, the disclosure of alternative values for the upper and lowerlimit of the permitted range of a parameter coupled with an indicatedthat one of said values is more preferred than the other, is to beconstrued as an implied statement that each intermediate value of saidparameter, lying between the more preferred and less preferred of saidalternatives is itself preferred to said less preferred value and alsoto each less preferred value and said intermediate value.

For all upper and/or lower boundaries of any parameters given herein,the boundary value is included in the value for each parameter. It willalso be understood that all combinations of preferred and/orintermediate minimum and maximum boundary values of the parametersdescribed herein in various embodiments of the invention may also beused to define alternative ranges for each parameter for various otherembodiments and/or preferences of the invention whether or not thecombination of such values has been specifically disclosed herein.

Thus for example a substance stated as present herein in an amount from0 to “x” (e.g. in units of mass and/or weight %) is meant (unless thecontext clearly indicates otherwise) to encompass both of twoalternatives, firstly a broader alternative that the substance mayoptionally not be present (when the amount is zero) or present only inan de-minimus amount below that can be detected. A second preferredalternative (denoted by a lower amount of zero in a range for amount ofsubstance) indicates that the substance is present, and zero indicatesthat the lower amount is a very small trace amount for example anyamount sufficient to be detected by suitable conventional analyticaltechniques and more preferably zero denotes that the lower limit ofamount of substance is greater than or equal to 0.001 by weight %(calculated as described herein).

It will be understood that the total sum of any quantities expressedherein as percentages cannot (allowing for rounding errors) exceed 100%.For example the sum of all components of which the composition of theinvention (or part(s) thereof) comprises may, when expressed as a weight(or other) percentage of the composition (or the same part(s) thereof),total 100% allowing for rounding errors. However where a list ofcomponents is non exhaustive the sum of the percentage for each of suchcomponents may be less than 100% to allow a certain percentage foradditional amount(s) of any additional component(s) that may not beexplicitly described herein.

In the present invention, unless the context clearly indicatesotherwise, an amount of an ingredient stated to be present in thecomposition of the invention when expressed as a weight percentage, iscalculated based on the total amount of monomers in the compositionbeing equivalent to 100% (thus for example components (a)+(b)+(c)+(d)total 100%). For convenience certain non monomer ingredients (such asfor example chain transfer agents (CTA)) which fall outside thedefinitions of any of components (a) to (d) may also be calculated asweight percentages based on total monomer (i.e. where the weight oftotal monomers alone is set at 100%). As the weight % of monomers (forexample for components (a) to (d)) by definition total 100% it will beseen that using monomer based weight % values for the non-monomeringredients (i.e. those components outside (a) to (d)) will mean thetotal percentages will exceed 100%. Thus amounts of non-monomeringredients expressed as monomer based weight percentages can beconsidered as providing a ratio for the weight amounts for theseingredients with respect to the total weight of monomers which is usedonly as a reference for calculation rather than as a strict percentage.Further ingredients are not excluded from the composition when(a)+(b)+(c)+(d) total 100% and weight percentages based on totalmonomers should not be confused with weight percentages of the totalcomposition.

The term “substantially” as used herein may refer to a quantity orentity to imply a large amount or proportion thereof. Where it isrelevant in the context in which it is used “substantially” can beunderstood to mean quantitatively (in relation to whatever quantity orentity to which it refers in the context of the description) therecomprises an proportion of at least 80%, preferably at least 85%, morepreferably at least 90%, most preferably at least 95%, especially atleast 98%, for example about 100% of the relevant whole. By analogy theterm “substantially-free” may similarly denote that quantity or entityto which it refers comprises no more than 20%, preferably no more than15%, more preferably no more than 10%, even more preferably no more than5%, most preferably no more than 2%, especially no more than 1.5%, forexample about 0% (e.g. completely absent or if present only in anundetectable amount) of the relevant whole.

The terms ‘optional substituent’ and/or ‘optionally substituted’ as usedherein (unless followed by a list of other substituents) signifies theone or more of following groups (or substitution by these groups):carboxy, sulpho, formyl, hydroxy, amino, imino, nitrilo, mercapto,cyano, nitro, methyl, methoxy and/or combinations thereof. Theseoptional groups include all chemically possible combinations in the samemoiety of a plurality (preferably two) of the aforementioned groups(e.g. amino and sulphonyl if directly attached to each other represent asulphamoyl group). Preferred optional substituents comprise: carboxy,sulpho, hydroxy, amino, mercapto, cyano, methyl, halo, trihalomethyland/or methoxy.

The synonymous terms ‘organic substituent’ and “organic group” as usedherein (also abbreviated herein to “organo”) denote any univalent ormultivalent moiety (optionally attached to one or more other moieties)which comprises one or more carbon atoms and optionally one or moreother heteroatoms. Organic groups may comprise organoheteryl groups(also known as organoelement groups) which comprise univalent groupscontaining carbon, which are thus organic, but which have their freevalence at an atom other than carbon (for example organothio groups).Organic groups may alternatively or additionally comprise organyl groupswhich comprise any organic substituent group, regardless of functionaltype, having one free valence at a carbon atom. Organic groups may alsocomprise heterocyclyl groups which comprise univalent groups formed byremoving a hydrogen atom from any ring atom of a heterocyclic compound:(a cyclic compound having as ring members atoms of at least twodifferent elements, in this case one being carbon). Preferably the noncarbon atoms in an organic group may be selected from: hydrogen, halo,phosphorus, nitrogen, oxygen, silicon and/or sulphur, more preferablyfrom hydrogen, nitrogen, oxygen, phosphorus and/or sulphur.

Most preferred organic groups comprise one or more of the followingcarbon containing moieties: alkyl, alkoxy, alkanoyl, carboxy, carbonyl,formyl and/or combinations thereof; optionally in combination with oneor more of the following heteroatom containing moieties: oxy, thio,sulphinyl, sulphonyl, amino, imino, nitrilo and/or combinations thereof.Organic groups include all chemically possible combinations in the samemoiety of a plurality (preferably two) of the aforementioned carboncontaining and/or heteroatom moieties (e.g. alkoxy and carbonyl ifdirectly attached to each other represent an alkoxycarbonyl group).

The term ‘hydrocarbo group’ as used herein is a sub-set of a organicgroup and denotes any univalent or multivalent moiety (optionallyattached to one or more other moieties) which consists of one or morehydrogen atoms and one or more carbon atoms and may comprise one or moresaturated, unsaturated and/or aromatic moieties. Hydrocarbo groups maycomprise one or more of the following groups. Hydrocarbyl groupscomprise univalent groups formed by removing a hydrogen atom from ahydrocarbon (for example alkyl). Hydrocarbylene groups comprise divalentgroups formed by removing two hydrogen atoms from a hydrocarbon, thefree valences of which are not engaged in a double bond (for examplealkylene). Hydrocarbylidene groups comprise divalent groups (which maybe represented by “R₂C═”) formed by removing two hydrogen atoms from thesame carbon atom of a hydrocarbon, the free valences of which areengaged in a double bond (for example alkylidene). Hydrocarbylidynegroups comprise trivalent groups (which may be represented by “RC≡”),formed by removing three hydrogen atoms from the same carbon atom of ahydrocarbon the free valences of which are engaged in a triple bond (forexample alkylidyne). Hydrocarbo groups may also comprise saturatedcarbon to carbon single bonds (e.g. in alkyl groups); unsaturated doubleand/or triple carbon to carbon bonds (e.g. in respectively alkenyl andalkynyl groups); aromatic groups (e.g. in aryl groups) and/orcombinations thereof within the same moiety and where indicated may besubstituted with other functional groups

The term ‘alkyl’ or its equivalent (e.g. ‘alk’) as used herein may bereadily replaced, where appropriate and unless the context clearlyindicates otherwise, by terms encompassing any other hydrocarbo groupsuch as those described herein (e.g. comprising double bonds, triplebonds, aromatic moieties (such as respectively alkenyl, alkynyl and/oraryl) and/or combinations thereof (e.g. aralkyl) as well as anymultivalent hydrocarbo species linking two or more moieties (such asbivalent hydrocarbylene radicals e.g. alkylene).

Any radical group or moiety mentioned herein (e.g. as a substituent) maybe a multivalent or a monovalent radical unless otherwise stated or thecontext clearly indicates otherwise (e.g. a bivalent hydrocarbylenemoiety linking two other moieties). However where indicated herein suchmonovalent or multivalent groups may still also comprise optionalsubstituents. A group which comprises a chain of three or more atomssignifies a group in which the chain wholly or in part may be linear,branched and/or form a ring (including spiro and/or fused rings). Thetotal number of certain atoms is specified for certain substituents forexample C_(1-N)organo, signifies a organo moiety comprising from 1 to Ncarbon atoms. In any of the formulae herein if one or more substituentsare not indicated as attached to any particular atom in a moiety (e.g.on a particular position along a chain and/or ring) the substituent mayreplace any H and/or may be located at any available position on themoiety which is chemically suitable and/or effective.

Preferably any of the organo groups listed herein comprise from 1 to 36carbon atoms, more preferably from 1 to 18. It is particularly preferredthat the number of carbon atoms in an organo group is from 1 to 12,especially from 1 to 10 inclusive, for example from 1 to 4 carbon atoms.

As used herein chemical terms (other than IUAPC names for specificallyidentified compounds) which comprise features which are given inparentheses—such as (alkyl)acrylate, (meth)acrylate and/or(co)polymer—denote that that part in parentheses is optional as thecontext dictates, so for example the term (meth)acrylate denotes bothmethacrylate and acrylate.

Certain moieties, species, groups, repeat units, compounds, oligomers,polymers, materials, mixtures, compositions and/or formulations whichcomprise and/or are used in some or all of the invention as describedherein may exist as one or more different forms such as any of those inthe following non exhaustive list: stereoisomers (such as enantiomers(e.g. E and/or Z forms), diastereoisomers and/or geometric isomers);tautomers (e.g. keto and/or enol forms), conformers, salts, zwitterions,complexes (such as chelates, clathrates, crown compounds,cyptands/cryptades, inclusion compounds, intercalation compounds,interstitial compounds, ligand complexes, organometallic complexes,non-stoichiometric complexes, π-adducts, solvates and/or hydrates);isotopically substituted forms, polymeric configurations [such as homoor copolymers, random, graft and/or block polymers, linear and/orbranched polymers (e.g. star and/or side branched), cross-linked and/ornetworked polymers, polymers obtainable from di and/or tri-valent repeatunits, dendrimers, polymers of different tacticity (e.g. isotactic,syndiotactic or atactic polymers)]; polymorphs (such as interstitialforms, crystalline forms and/or amorphous forms), different phases,solid solutions; and/or combinations thereof and/or mixtures thereofwhere possible. The present invention comprises and/or uses all suchforms which are effective as defined herein.

Polymers of the present invention may be prepared by one or moresuitable polymer precursor(s) which may be organic and/or inorganic andcomprise any suitable (co)monomer(s), (co)polymer(s) [includinghomopolymer(s)] and mixtures thereof which comprise moieties which arecapable of forming a bond with the or each polymer precursor(s) toprovide chain extension and/or cross-linking with another of the or eachpolymer precursor(s) via direct bond(s) as indicated herein.

Polymer precursors of the invention may comprise one or more monomer(s),oligomer(s), polymer(s); mixtures thereof and/or combinations thereofwhich have suitable polymerisable functionality. It will be understoodthat unless the context dictates otherwise term monomer as used hereinencompasses the term polymer precursor and does not necessarily excludemonomers that may themselves be polymeric and/or oligomeric incharacter.

A monomer is a substantially monodisperse compound of a low molecularweight (for example less than one thousand daltons) which is capable ofbeing polymerised.

A polymer is a polydisperse mixture of macromolecules of large molecularweight (for example many thousands of daltons) prepared by apolymerisation method, where the macromolecules comprises the multiplerepetition of smaller units (which may themselves be monomers, oligomersand/or polymers) and where (unless properties are critically dependenton fine details of the molecular structure) the addition or removal oneor a few of the units has a negligible effect on the properties of themacromolecule.

A oligomer is a polydisperse mixture of molecules having an intermediatemolecular weight between a monomer and polymer, the molecules comprisinga small plurality of monomer units the removal of one or a few of whichwould significantly vary the properties of the molecule.

Depending on the context the term polymer may or may not encompassoligomer.

The polymer precursor of and/or used in the invention may be prepared bydirect synthesis or (if the polymeric precursor is itself polymeric) bypolymerisation. If a polymerisable polymer is itself used as a polymerprecursor of and/or used in the invention it is preferred that such apolymer precursor has a low polydispersity, more preferably issubstantially monodisperse, to minimise the side reactions, number ofby-products and/or polydispersity in any polymeric material formed fromthis polymer precursor. The polymer precursor(s) may be substantiallyun-reactive at normal temperatures and pressures.

Except where indicated herein polymers and/or polymeric polymerprecursors of and/or used in the invention can be (co)polymerised by anysuitable means of polymerisation well known to those skilled in the art.Examples of suitable methods comprise: thermal initiation; chemicalinitiation by adding suitable agents; catalysis; and/or initiation usingan optional initiator followed by irradiation, for example withelectromagnetic radiation (photo-chemical initiation) at a suitablewavelength such as UV; and/or with other types of radiation such aselectron beams, alpha particles, neutrons and/or other particles.

The substituents on the repeating unit of a polymer and/or oligomer maybe selected to improve the compatibility of the materials with thepolymers and/or resins in which they may be formulated and/orincorporated for the uses described herein. Thus the size and length ofthe substituents may be selected to optimise the physical entanglementor interlocation with the resin or they may or may not comprise otherreactive entities capable of chemically reacting and/or cross linkingwith such other resins as appropriate.

Another aspect of the invention broadly provides a coating compositioncomprising the polymers and/or beads of the present invention and/or asdescribed herein.

A further aspect of the invention provides a coating obtained orobtainable from a coating composition of the present invention.

A yet other aspect of the invention broadly provides a substrate and/orarticle having coated thereon an (optionally cured) coating compositionof the present invention.

A yet further aspect of the invention broadly provides a method of usingpolymers of the present invention and/or as described herein to preparea coating composition.

A still further aspect of the invention broadly provides a method forpreparing a coated substrate and/or article comprising the steps ofapplying a coating composition of the present invention to the substrateand/or article and optionally curing said composition in situ to form acured coating thereon. The curing may be by any suitable means, such asthermally, by radiation and/or by use of a cross-linker.

Preferred coating compositions are solvent coating compositions oraqueous coating compositions, more preferably are aqueous coatingcompositions.

Optionally aqueous coating compositions may also comprise a co-solvent.A co-solvent, as is well known in the coating art, is an organic solventemployed in an aqueous composition to ameliorate the dryingcharacteristics thereof, and in particular to lower its minimum filmforming temperature. The co-solvent may be solvent incorporated or usedduring preparation of polymers of the invention or may have been addedduring formulation of the aqueous composition.

The compositions of the invention are particularly useful as or forproviding the principle component of coating formulations (i.e.composition intended for application to a substrate without furthertreatment or additions thereto) such as protective or decorative coatingcompositions (for example paint, lacquer or varnish) wherein aninitially prepared composition optionally may be further diluted withwater and/or organic solvents, and/or combined with further ingredientsor may be in more concentrated form by optional evaporation of waterand/or organic components of the liquid medium of an initially preparedcomposition.

The compositions of the invention may be used in various applicationsand for such purposes may be optionally further combined or formulatedwith other additives and/or components, such as defoamers, rheologycontrol agents, thickeners, dispersing and/or stabilizing agents(usually surfactants and/or emulsifiers), wetting agents, fillers,extenders, fungicides, bacteriocides, coalescing and wetting solvents orco-solvents (although solvents are not normally required), plasticisers,anti-freeze agents, waxes, colorants, pigments, dyes, heat stabilisers,levelling agents, anti-cratering agents, fillers, sedimentationinhibitors, UV absorbers, antioxidants, reactive diluents, neutralisingagents, adhesion promoters and/or any suitable mixtures thereof.

The aforementioned additives and/or components and the like may beintroduced at any stage of the production process or subsequently. It ispossible to include fire retardants (such as antimony oxide) to enhancefire retardant properties.

The compositions of the invention may also be blended with otherpolymers such as vinyl polymers, alkyds (saturated or unsaturated),polyesters and or polyurethanes.

The coating composition of the invention may be applied to a variety ofsubstrates including wood, board, metals, stone, concrete, glass, cloth,leather, paper, plastics, foam and the like, by any conventional methodincluding brushing, dipping, flow coating, spraying, and the like. Thecoating composition of the invention may also be used to coat theinterior and/or exterior surfaces of three-dimensional articles. Thecoating compositions of the invention may also be used, appropriatelyformulated if necessary, for the provision of films, polishes,varnishes, lacquers, paints, inks and adhesives. However, they areparticularly useful and suitable for providing the basis of protectivecoatings for substrates that comprise wood (e.g. wooden floors),plastics, polymeric materials, paper and/or metal.

The carrier medium may be removed from the compositions of the inventiononce they have been applied to a substrate by being allowed to drynaturally at ambient temperature, or the drying process may beaccelerated by heat. Crosslinking can be developed by allowing to standfor a prolonged period at ambient temperature (several days) or byheating at an elevated temperature (e.g. 50° C.) for a much shorterperiod of time.

Many other variations embodiments of the invention will be apparent tothose skilled in the art and such variations are contemplated within thebroad scope of the present invention.

Further aspects of the invention and preferred features thereof aregiven in the claims herein.

Tests

Minimum Film Forming Temperature

The minimum film forming temperature (MFFT) of a dispersion as usedherein is the temperature where the dispersion forms a smooth and crackfree coating or film using DIN 53787 and when applied using a Sheen MFFTbar SS3000.

Spot Tests

Coating films formed by blends of the invention can be tested in wellknown conventional spot tests (such as ASTM D1308-02e1) to determine theresistance of the film to various liquid reagents such as water,ethanol, detergent (e.g. that available commercially from Unilever underthe trade mark Andy) and coffee. In one such test a standard volume(e.g. 0.5 ml) of the liquid reagent may be applied to the film to form aspot thereon (e.g. by pipette) which is then covered with a watch glass.After the time specified (e.g. in the tables herein) the film can beassessed and rated visually on a scale of 1 to 5 as described below.

Koening Hardness

Koenig hardness as used herein is a standard measure of hardness, beinga determination of how the viscoelastic properties of a film formed fromthe dispersion slows down a swinging motion deforming the surface of thefilm, and is measured according to DIN 53157 NEN5319.

Glass Transition Temperature (Tg)

As is well known, the glass transition temperature of a polymer is thetemperature at which it changes from a glassy, brittle state to aplastic, rubbery state. The glass transition temperatures may bedetermined experimentally using Differential Scanning calorimetry (DSC),taking the peak of the derivative curve as Tg, or calculated from theFox equation. Thus the Tg, in degrees Kelvin, of a copolymer having “n”copolymerised comonomers is given by the weight fractions W of eachcomonomer type and the Tgs of the homopolymers (in degrees Kelvin)derived from each comonomer according to the equation:1/Tg=W ₁ /Tg ₁ +W ₂ /Tg ₂ + . . . W _(n) /Tg _(n)

The calculated Tg in degrees Kelvin may be readily converted to ° C.

Solids Content

The solids content of an aqueous dispersion of the invention is usuallywithin the range of from about 20 to 65 wt-% on a total weight basis,more usually 30 to 55 wt-%. Solids content can, if desired, be adjustedby adding water or removing water (e.g. by distillation orultrafiltration).

pH Value

The pH value of the dispersion of the invention can be from 2 to 10 andmostly is from 6 to 9.5.

Blocking

Block Resistance Measurement [Includes Blocking and Early Blocking]:

Step 1: Blocking:

A 100 micron wet film of the aqueous emulsion of the invention to which10% butyldiglycol is added is cast on to a paper substrate and dried for16 hours at 52° C.

Step 1: Early Blocking:

A 250 micron wet film of the aqueous emulsion of the invention to which10% butyldiglycol was added, is cast on to a paper substrate and driedfor 24 hours at room temperature.

Step 2: Blocking and Early Blocking:

After cooling down to room temperature two pieces of coated film areplaced with the coated side against each other under a load of 1Kg/cm.sup.2 for 4 hours at 52° C. After this time interval the load onthe samples is removed and the samples are left to cool down to roomtemperature (22+−2° C.). When the two coatings can be removed from eachother without any damage to the film (do not stick) the block resistanceis very good and assessed as a 5. When they however completely sticktogether, block resistance is very bad and assessed as a 0.

Gas Chromatography Mass Spectrometry (GCMS)

To confirm polymerisation is substantially complete the content of freeitaconate ester monomers content can be determined by GCMS. The GCMSanalyses were performed on a Trace GC-DSQ MS (Interscience, Breda, theNetherlands) equipped with a CTC combi Pal robotic autosampler for headspace has been used. The carrier gas was Helium and a CP Sil 5 lowbleed/MS, 25 m×0.25 mm i.d., 1.0 μm (CP nr. 7862) column has been used.

The GC-oven was programmed from 50° C. (5 min) followed by differentsequential temperature ramps of 5° C./min to 70° C. (0 min), 15° C./minto 220° C. (0 min), and ending with 25° C./min to 280° C. (10 min). Acontinuous Helium flow of 1.2 ml/min was used. A hot split injection at300° C. was performed on a programmed temperature vaporizer (PTV). Theinjection volume was 1 μl. The MS transfer line and ion source were bothkept at 250° C. The samples were measured with single ion monitoring(SIM). For the specific case of dibutyl itaconate (DBI) the masses 127.0and 59.0 Da were used, for the internal standard (iso butyl acrylate)the masses 55.0 and 73.0 were applied. The sample solutions wereapproximately 500 mg in 3 ml of internal standard solution (iso butylacrylate in acetone). The calibration was performed with 5 differentconcentration levels from 0 to 500 ppm. The calculation was performedusing Microsoft Excel with a linear calibration curve.

Molecular Weight

Unless the context clearly dictates otherwise the term molecular weightof a polymer or oligomer as used herein denotes weight average molecularweight (also denoted as M_(w)). M_(w) may be measured by any suitableconventional method for example by Gas Phase Chromatography(GPC—performed similarly to the GCMS method described above) and/or bythe SEC method described below. GPC method is preferred

Determination of Molecular Weight of a Polymer Using SEC

The molecular weight of a polymer may also be determined using SizeExclusion Chromatography (SEC) with tetrahydrofuran as the eluent orwith 1,1,1,3,3,3 hexafluoro isopropanol as the eluent.

1) tetrahydrofuran

The SEC analyses were performed on an Alliance Separation Module (Waters2690), including a pump, auto injector, degasser, and column oven. Theeluent was tetrahydrofuran (THF) with the addition of 1.0 vol % aceticacid. The injection volume was 150 μl. The flow was established at 1.0ml/min. Three PL MixedB (Polymer Laboratories) with a guard column (3 μmPL) were applied at a temperature of 40° C. The detection was performedwith a differential refractive index detector (Waters 410). The samplesolutions were prepared with a concentration of 20 mg solids in 8 ml THF(+1 vol % acetic acid), and the samples were dissolved for a period of24 hours. Calibration is performed with eight polystyrene standards(polymer standard services), ranging from 500 to 4,000,000 g/mol. Thecalculation was performed with Millennium 32 software (Waters) with athird order calibration curve. The obtained molar masses are polystyreneequivalent molar masses (g/mol).

2) 1,1,1,3,3,3 hexafluoro isopropanol

The SEC analyses were performed on a Waters Alliance 2695 (pump,degasser and autosampler) with a Shodex RI-101 differential refractiveindex detector and Shimadzu CTO-20AC column oven. The eluent was1,1,1,3,3,3 hexafluoro isopropanol (HFIP) with the addition of 0.2Mpotassium trifluoro acetate (KTFA). The injection volume was 50 μl. Theflow was established at 0.8 ml/min. Two PSS PFG Linear XL columns(Polymer Standards Service) with a guard column (PFG PSS) were appliedat a temperature of 40° C. The detection was performed with adifferential refractive index detector. The sample solutions wereprepared with a concentration of 5 mg solids in 2 ml HFIP (+0.2M KTFA),and the samples were dissolved for a period of 24 hours. Calibration isperformed with eleven polymethyl methacrylate standards (polymerstandard services), ranging from 500 to 2,000,000 g/mol. The calculationwas performed with Empower Pro software (Waters) with a third ordercalibration curve. The molar mass distribution is obtained viaconventional calibration and the molar masses are polymethylmethacrylate equivalent molar masses (g/mol).

Standard Conditions

As used herein, unless the context indicates otherwise, standardconditions (e.g. for drying a film) means a relative humidity of 50%±5%,ambient temperature (which denotes herein a temperature of 23° C.±2°)and an air flow of ≦(less than or equal to) 0.1 m/s.

The following examples are provided to further illustrate the processesand compositions of the present invention. These examples areillustrative only and are not intended to limit the scope of theinvention in any way. Unless otherwise specified all parts, percentages,and ratios are on a weight basis. The prefix C before an exampleindicates that it is comparative.

Various registered trademarks, other designations and/or abbreviationsare used herein to denote some of ingredients used to prepare polymersand compositions of the invention. These are identified below bychemical name and/or trade-name and optionally their manufacturer orsupplier from whom they are available commercially. However where achemical name and/or supplier of a material described herein is notgiven it may easily be found for example in reference literature wellknown to those skilled in the art: such as: ‘McCutcheon's Emulsifiersand Detergents’, Rock Road, Glen Rock, N.J. 07452-1700, USA, 1997 and/orHawley's Condensed Chemical Dictionary (14th Edition) by Lewis, RichardJ., Sr.; John Wiley & Sons.

In the examples the following abbreviations/monomers may be used:

BA=n-butyl acrylate (may be biorenewable)

BMA=n-butyl methacrylate (may be prepared using bio-renewable alkanols)

DBI denotes di(n-butyl) itaconate (also known as dibutyl2-methylidenebutanedioate) (may be bio-renewable)

DDM denotes n-dodecyl mercaptane

DMI=dimethyl itaconate (may be bio-renewable)

DMW denotes dematerialized water

EDTA=ethylene diamine tetraacetic acid

HFIP denotes hexafluoro isopropanol

KTFA denotes potassium trifluoro actetate

MMA=methyl methacrylate (may be prepared using bio-renewable alkanols)

MAA=methacrylic acid (may be biorenewable)

NS denotes sodium sulfate

PAA denotes polyacrylic acid

STY denotes styrene;

D(iB)I denotes di(iso-butyl) itaconate (also known asdi(tert-butyl)itaconate)

DPI denotes di(pentyl) itaconate

DHI denotes di(hexyl) itaconate

DHpI denotes di(heptyl) itaconate

DOI denotes di(n-octyl) itaconate

D(EH)I denotes di(2-ethylhexyl) itaconate

DDI denotes di(decyl) itaconate

DBzI denotes di(benzyl) itaconate

DPhI denotes di(phenyl) itaconate

BPI denotes butyl pentyl itaconate

BHI denotes butyl hexyl itaconate

HOI denotes hexyl n-octyl itaconate

IA denotes itaconic acid

MSA denotes the sulphonic acid of α-methyl styrene

DPrI denotes di(propyl) itaconate

CEA denotes beta carboxy ethyl acrylate

PA denotes propyl acrylate

OA denotes n-ocyl acrylate

MBI denotes the mono acid butyl itaconate (i.e. half ester)

IAn denotes itaconic anhydride

MMaIA denotes methylene malonic acid,

MalAn denotes maleic anhydride, i

PHEMA denotes phosphated hydroxylethyl methacrylate

AMPS denotes 2-acrylamido-2-methylpropane sulfonic acid

URED denotes the monomer N-[2-(2-Oxo-1-imidazolidinyl)ethyl]methacrylate

MSTY denotes alpha methyl styrene

EXAMPLES 1 TO 4 Vinyl Oligomer-Polymers Example 1 Oligomer 1A

To a round-bottomed flask equipped with a condenser, thermometer andmechanical stirrer 549.0 parts of water and 0.7 parts of Aerosol GPGwere charged. This mixture was heated to 70° C. At 70° C. 10% of amonomer feed consisting of 100.8 parts of water, 44.1 parts of methylmethacrylate, 136.2 parts of dimethyl itaconate, 14.6 parts of diacetoneacrylamide, 24.3 parts of diethyl itaconate, 24.3 parts of methacrylicacid, 2.0 parts of Aerosol GPG, and 5.8 parts of 3-mercaptopropionicacid was added and the reactor contents were further heated to 85° C. At80° C. a solution consisting of 0.2 parts of ammonium persulphate and11.3 parts of water was added.

At 85° C., the remainder of the monomer feed was added over a period of260 minutes. A catalyst feed, comprising 0.5 parts of ammoniumpersulphate and 33.5 parts of water was fed to the reactor in period of250 minutes. At the end of the addition of the monomer feed 5.0 parts ofwater were used to rinse the feed tank and were added to the reactor. Atemperature of 85° C. was maintained for 20 minutes after which thereaction mixture was cooled to 80° C. At 80° C. the emulsion wasneutralized using 19.4 parts of a 25% solution of ammonia in water mixedwith 21.2 parts of water. The reaction mixture was subsequently kept at80° C. for another 20 minutes before it was cooled to room temperature.The solids content of the emulsion was adjusted to 25% with water.

The resulting emulsion had a solids content of 25.1% and a pH of 8.0.

Polymer Emulsion 1B

To a round-bottomed flask equipped with a condenser, thermometer andmechanical stirrer were added 15.2 parts of water and 498.1 parts of anoligomer prepared as described in Oligomer 1A. The contents of thereactor were heated to 60° C.

33% of a monomer feed consisting of 13.9 parts of water, 13.9 parts ofdiethyl itaconate, 156.0 parts of dibutyl itaconate, 135.9 parts ofbutyl acrylate, and 6.2 parts of diacetone acrylamide was added afterwhich the emulsion was stirred for 15 minutes. Next, 0.4 parts of a 70wt-% slurry of t-butyl hydroperoxide, and 1.2 parts of water, followedby 33% of a solution of 0.7 parts of i-ascorbic acid in 13.8 parts ofwater.

After the temperature had reached 66° C., the batch was stirred for 10minutes, 45.5 parts of water were added and the batch was cooled to 60°C. Next, 50% of the remaining monomer feed was added, followed by 0.4parts of a 70 wt-% slurry of t-butyl hydroperoxide, 1.2 parts of water,and 50% of the remaining i-ascorbic acid solution. After the temperaturehad reached 62° C., the batch was stirred for 10 minutes, 56.4 parts ofwater were added and the batch was cooled to 60° C. The remainder of themonomer feed and 5.1 parts of water were added, followed by 0.4 parts ofa 70 wt-% slurry of t-butyl hydroperoxide, 1.8 parts of water, and theremaining i-ascorbic acid solution. After the temperature had reached61° C. after approximately 15 minutes, the batch was stirred for anadditional 10 minutes. Next, 0.5 parts of a 70 wt-% slurry of t-butylhydroperoxide, and 0.7 parts of water were added, followed by a solutionof 0.3 parts of i-ascorbic acid in 4.6 parts of water. After theemulsion was allowed to stir for 30 minutes, the batch was cooled to 30°C. after which 6.2 parts of adipic dihydrazide and 17.8 parts of waterwere added. The solids content of the emulsion was corrected to 44%using water.

The resulting emulsion had a solids content of 44.0% and a pH of 7.8.

Example 2 Oligomer 2A

To a round-bottomed flask equipped with a condenser, thermometer andmechanical stirrer 1087.6 parts of water and 1.3 parts of Aerosol GPGwere charged. This mixture was heated to 70° C. At 70° C. 10% of amonomer feed consisting of 211.7 parts of water, 416.9 parts of methylmethacrylate, 39.0 parts of diacetone acrylamide, 32.2 parts ofmethacrylic acid, 3.9 parts of Aerosol GPG, and 11.7 parts of laurylmercaptane was added and the reactor contents were further heated to 85°C. At 80° C. a solution consisting of 0.4 parts of ammonium persulphateand 28.8 parts of water was added.

At 85° C., the remainder of the monomer feed was added over a period of60 minutes. A catalyst feed, comprising 1.0 parts of ammoniumpersulphate and 67.3 parts of water was fed to the reactor in period of70 minutes. At the end of the addition of the monomer feed 31.3 parts ofwater were used to rinse the feed tank and were added to the reactor. Atemperature of 85° C. was maintained for 20 minutes after which thereaction mixture was cooled to 80° C. At 80° C. the emulsion wasneutralized using 24.4 parts of a 25% solution of ammonia in water mixedwith 41.4 parts of water. The reaction mixture was subsequently kept at80° C. for another 20 minutes before it was cooled to room temperature.The solids content of the emulsion was adjusted to 25% with water.

The resulting emulsion had a solids content of 25.1% and a pH of 8.0.

Polymer Emulsion 2B

To a round-bottomed flask equipped with a condenser, thermometer andmechanical stirrer were added: 1.50 parts of water, and 49.11 parts ofan oligomer prepared as described in Oligomer 2A above. The contents ofthe reactor were heated to 60° C.

33% of a monomer feed consisting of 2.77 parts of dimethyl itaconate,11.08 parts of butyl acrylate, and 13.84 parts of dibutyl itaconate wasadded after which the emulsion was stirred for 15 minutes. Next, 0.03parts of a 70 wt-% slurry of t-butyl hydroperoxide, and 0.13 parts ofwater were added, followed by 30% of a solution of 0.07 parts ofi-ascorbic acid in 2.73 parts of water. After the temperature hadreached 73° C., the batch was stirred for 10 minutes and cooled to 60°C. Next, 50% of the remaining monomer feed was added, followed by 4.74parts of water, and the emulsion was allowed to stir for 15 minutes. Aslurry of 0.03 parts of a 70 wt-% slurry of t-butyl hydroperoxide, 0.13parts of water was added followed by 30% of the i-ascorbic acidsolution. The temperature reached 69° C. after which the mixture wasmixed for another 10 minutes. 6.71 parts of water were added and thebatch was cooled to 60° C. Next, the remainder of the monomer feed wasadded, the mixture was stirred for 15 minutes and 0.03 parts of a 70wt-% slurry of t-butyl hydroperoxide, and 0.13 parts of water wereadded, followed by 30% of the i-ascorbic acid solution. After thereaction mixture had reached a temperature of 68° C., the emulsion wasallowed to stir for 30 minutes at this temperature after which theemulsion was cooled to 65° C.

A second monomer feed, consisting of 0.06 parts of diacetone acrylamide,2.03 parts of butyl acrylate, and 0.98 parts of methyl methacrylate, wasadded. Next, 0.01 parts of a 70 wt-% slurry of t-butyl hydroperoxide,and 0.04 parts of water were added, followed by the remaining i-ascorbicacid solution. The temperature was allowed to drift for 15 minutes,after which the batch was again cooled to 65° C. At 65° C. a slurry of0.04 parts of a 70 wt-% slurry of t-butyl hydroperoxide, and 0.06 partsof water was added, followed by a solution of 0.03 parts of i-ascorbicacid in 1.30 parts of water. The batch was cooled to 30° C. and 0.50parts of water were added. At 30° C. 0.61 parts of adipic dihydrazidewere added together with 0.90 parts of water. The solids content of theemulsion was corrected to 44% using water.

The resulting emulsion had a solids content of 44.0% and a pH of 7.8.

Example 3 Polymer Emulsion 3B

To a round-bottomed flask equipped with a condenser, thermometer andmechanical stirrer, were added 1.50 parts of water, and 49.11 parts ofan oligomer prepared as described in Oligomer 2A above. The contents ofthe reactor were heated to 60° C.

33% of a monomer feed consisting of 2.77 parts of monobutyl itaconate,11.08 parts of butyl acrylate, and 6.41 parts of dimethyl itaconate,7.43 parts of dibutyl itaconate was added after which the emulsion wasstirred for 15 minutes. Next, 0.03 parts of a 70 wt-% slurry of t-butylhydroperoxide, and 0.13 parts of water were added, followed by 30% of asolution of 0.07 parts of i-ascorbic acid in 2.73 parts of water. Afterthe temperature had reached 73° C., the batch was stirred for 10 minutesand cooled to 60° C. Next, 50% of the remaining monomer feed was added,followed by 4.74 parts of water, and the emulsion was allowed to stirfor 15 minutes. A slurry of 0.03 parts of a 70 wt-% slurry of t-butylhydroperoxide, 0.13 parts of water was added followed by 30% of thei-ascorbic acid solution. The temperature reached 69° C. after which themixture was mixed for another 10 minutes. 6.71 parts of water were addedand the batch was cooled to 60° C. Next, the remainder of the monomerfeed was added, the mixture was stirred for 15 minutes and 0.03 parts ofa 70 wt-% slurry of t-butyl hydroperoxide, and 0.13 parts of water wereadded, followed by 30% of the i-ascorbic acid solution. After thereaction mixture had reached a temperature of 68° C., the emulsion wasallowed to stir for 30 minutes at this temperature after which theemulsion was cooled to 65° C.

A second monomer feed, consisting of 0.06 parts of diacetone acrylamide,2.03 parts of butyl acrylate, and 0.98 parts of methyl methacrylate, wasadded. Next, 0.01 parts of a 70 wt-% slurry of t-butyl hydroperoxide,and 0.04 parts of water were added, followed by the remaining i-ascorbicacid solution. The temperature was allowed to drift for 15 minutes,after which the batch was again cooled to 65° C. At 65° C. a slurry of0.04 parts of a 70 wt-% slurry of t-butyl hydroperoxide, and 0.06 partsof water was added, followed by a solution of 0.03 parts of i-ascorbicacid in 1.30 parts of water. The batch was cooled to 30° C. and 0.50parts of water were added. At 30° C. 0.61 parts of adipic dihydrazidewere added together with 0.90 parts of water. The solids content of theemulsion was corrected to 44% using water.

The resulting emulsion had a solids content of 44.0% and a pH of 7.8.

Example 4

An emulsion was prepared exactly as described in Example 3 above exceptin preparing the polymer component (Polymer Emulsion 4B) the monomerfeed consisted of: 11.08 parts of butyl acrylate, 4.86 parts of dimethylitaconate, and 8.98 parts of dibutyl itaconate.

The resulting emulsion had a solids content of 44.0% and a pH of 7.8.

Further Examples Examples 5 to 14

Further examples for the various embodiments can be prepared accordingthe Common method, F below and with reference to Table 1. Thepercentages in the tables are mostly quoted to the nearest percentageand/or to 2 significant figures and thus may not total 100% due torounding errors.

Common Method F for Oligomer/Polymer

The total weight of monomer used in Examples below can be the same asthe total amount used to prepare each part of Example 1 (oligomer Ex 1Aand polymer Ex 1B). So for convenience the amount of monomers used inthese examples is expressed as a weight percent of the respective totalmonomers for the oligomer (in method F1) and the polymer (in method F2).

Oligomer (F1)

A monomer feed (used to prepare the oligomer) consists of the sameingredients described in Example 1A (or with consequent modification),other than the monomers which can be: z3% of Monomer Z3, y3% of MonomerY3, x3% of Monomer X3 and/or w3% of Monomer W3. To the equipmentdescribed in Example 1A under the conditions described therein themonomer feed can be added and the reaction continued as described inExample 1A (or with consequent modification) with reference to Table 1to obtain oligomer analogous to that described in Example 1A which canbe used in step F2 below.

Polymer Emulsion (F2)

A monomer feed (used to prepare the polymer) consists of the sameingredients described in Example 1B (or with consequent modification),other than the monomers which can be: z4% of Monomer Z4, y4% of MonomerY4, X4% of Monomer X4 and/or w4% of Monomer W4. To the equipmentdescribed in Example 1B under the conditions described therein themonomer feed can be added together with an oligomer from step F1 and thereaction continued as described in Example 1B (or with consequentmodification) with reference to Table 1 to obtain oligomer-polymersanalogous to that described in Example 1.

The total amount of monomer of Formula 1 (as a percentage T of the totalamount of monomers C+D is also given in Table 1)

TABLE 1 Examples 5 to 14 - oligomer-polymers (see method F1 and F2) R′ T% (C (of Oligomer C (% of C) Polymer D (% of D) to C + Ex z3% Z3 y3% Y3x3% X3 w3% W3 z4% Z4 y4% Y4 x4% X4 w4% W4 D) D) 5 20 AA 80 EMA — — — —80 D 20 DEI — — — —  5:95 76 (EH)I 6 10 AA 10 DBI 70 DMI 10  DAAM 50 DBI40 BA 10 DAAM — — 10:90 46 7 5 MSA 70 MMA 20 DEI 5 DAAM 30 DOI 55 OA  5DAAM 10 BA 30:70 21 8 20 CEA 50 MA 30 DMI — — 40 DHI 60 BMA — — — —40:60 24 9 5 MBI 20 EA 70 DPrI 5 DAAM 50 DPI 40 BA 10 DEI — — 50:50 2510 3 IA 10 MMA 80 DBI 7 DAAM 50 DMI 40 EA 10 MA 60:40 48 11 4 IAn 30 MMA60 DBI 6 DAAM 50 DBI 40 PA 10 MMA 70:30 57 12 5 MMaIA 50 MMA 40 DPI 5DAAM 50 DBI 40 DMI 10 BMA 75:25 42.5 13 2 PHEMA 60 MMA 30 DMI 8 DAAM 50DBI 20 EA 20 BMA 10 DAAM 50:50 25 14 40 AMPS 20 MMA 40 DBI — — 50 DEI 40MMA 10 BMA 50:50 20

Further Examples 15 to 21 and Comparative Examples Comp I to III Example15 DBI Polymer Containing Wet-Adhesion Promoting Monomer

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer were charged 559.2 parts of demineralized water, 5.5 parts ofsodium bicarbonate, 29.4 parts of a 30 wt-% solution of sodium laurylsulphate in water, and 1.1 parts of sodium persulphate. The reactorcontents were heated to 70° C. At 50° C., 10% of a monomer feedconsisting of 510.3 parts of demineralized water, 12.5 parts of a 30wt-% solution of sodium lauryl sulphate in water, 516.7 parts of butylacrylate, 33.0 parts of methacrylic acid, 494.7 parts of dibutylitaconate, and 110.0 parts of a 50 wt-% solution ofN-(2-methacryloyloxyethyl)ethylene urea in water (Plex 6852-0, ex.Evonik), was added. Due to the exothermic nature of the polymerizingmonomers, the temperature increased to 85° C. (if the exotherm would beinsufficient the mixture could be heated slightly to reach a temperatureof 85° C.). At 85° C., the monomer feed, comprising the remaining 90% ofthe original feed, and the initiator feed, consisting of 124.5 parts ofdemineralized water, 4.4 parts of sodium persulphate, and 2.2 parts of a30 wt-% solution of sodium lauryl sulphate in water, were started. Bothfeeds were added over a period of 120 minutes. At the end of the monomerfeed, the feed tank was rinsed with 19.7 parts of demineralized waterand the mixture was stirred at 85° C. for another 35 minutes.

Next, the emulsion was cooled to 45° C., and a solution of 0.7 parts ofiso-ascorbic acid in 12.5 parts of demineralized water was added,followed by 1.0 part of a 70 wt-% solution of t-butyl hydroperoxide inwater, 1.5 parts of demineralized water, and 0.3 parts of a 30 wt-%solution of sodium lauryl sulphate in water. The entire reactor contentswere stirred for 30 minutes at 45° C.

The emulsion was cooled to room temperature, and 55.0 parts of an equalmixture of a 25% solution of ammonia in water and demineralized waterwere added. The solids content of the emulsion was adjusted to 45% usingdemineralized water.

Example 16 DBI and Styrene Containing Polymer

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer were charged 644.0 parts of demineralized water, 0.5 parts ofsodium bicarbonate, 13.3 parts of a 30 wt-% solution of sodium laurylsulphate in water, and 0.8 parts of sodium persulphate. The reactorcontents were heated to 80° C. and stirred for 5 minutes at 80° C. Next,10% of a monomer feed, consisting of 132.9 parts of demineralized water,13.0 parts of a 30 wt-% solution of sodium lauryl sulphate in water,23.3 parts of methacrylic acid, 280.1 parts of dibutyl itaconate, and280.1 parts of styrene, was added, after the temperature rose toapproximately 90° C. due to the exothermic nature of the polymerization.As soon as the temperature of 90° C. was reached, the remaining monomerfeed and the initiator feed, consisting of 58.7 parts of demineralizedwater, 2.5 parts of sodium persulphate, and 3.7 parts of a 30 wt-%solution of sodium lauryl sulphate in water, were started. Both feedswere added over a period of 2 hours. At the end of the monomer feed thefeed tank was rinsed with 10.4 parts of demineralized water. Thetemperature of the reactor contents were cooled to 80° C., after which asolution of 1.8 parts of iso-ascorbic acid dissolved in 26.5 parts ofdemineralized water (which was brought to a pH of 8.5 using an ammoniasolution) was fed over a period of 30 minutes, during which a mixture of2.8 parts of t-butyl hydroperoxide and 5.6 parts of demineralized waterwas added in two shots; one at the start of the iso-ascorbic acid feedand 15 minutes later.

At the end of the feed, the mixture was stirred at 80° C. for 30minutes, and the pH was raised to 7.2 using a 25 wt-% solution ofammonia in water. After stirring for another 30 minutes, the batch wascooled to room temperature. The solids content was adjusted to 40% usingdemineralized water.

Comparative Example Comp I BA and Styrene Containing Polymer

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer were charged 639.5 parts of demineralized water, 0.5 parts ofsodium bicarbonate, and 13.3 parts of a 30 wt-% solution of sodiumlauryl sulphate in water. The reactor contents were heated to 80° C.,after which a solution of 0.8 parts of sodium persulphate in 4.5 partsof demineralized water were added and stirred for 5 minutes at 80° C.Next, 10% of a monomer feed, consisting of 132.9 parts of demineralizedwater, 13.0 parts of a 30 wt-% solution of sodium lauryl sulphate inwater, 23.3 parts of methacrylic acid, 280.1 parts of butyl acrylate,and 280.1 parts of styrene, was added, after the temperature rose toapproximately 90° C. due to the exothermic nature of the polymerization.As soon as the temperature of 90° C. was reached, the remaining monomerfeed and the initiator feed, consisting of 58.7 parts of demineralizedwater, 2.5 parts of sodium persulphate, and 3.7 parts of a 30 wt-%solution of sodium lauryl sulphate in water, were started. Both feedswere added over a period of 2 hours. At the end of the monomer feed thefeed tank was rinsed with 10.4 parts of demineralized water. Thetemperature of the reactor contents were cooled to 80° C., after which asolution of 1.8 parts of iso-ascorbic acid dissolved in 26.5 parts ofdemineralized water (which was brought to a pH of 8.5 using an ammoniasolution) was fed over a period of 30 minutes, during which a mixture of2.8 parts of t-butyl hydroperoxide and 5.6 parts of demineralized waterwas added in two shots; one at the start of the iso-ascorbic acid feedand 15 minutes later.

At the end of the feed, the mixture was stirred at 80° C. for 30minutes, and the pH was raised to 7.2 using a 25 wt-% solution ofammonia in water. After stirring for another 30 minutes, the batch wascooled to room temperature. The solids content was adjusted to 40% usingdemineralized water.

Example 17 DBI and MMA Containing Polymer

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer were charged 639.5 parts of demineralized water, 0.5 parts ofsodium bicarbonate, and 13.3 parts of a 30 wt-% solution of sodiumlauryl sulphate in water. The reactor contents were heated to 80° C.,after which a solution of 0.8 parts of sodium persulphate in 4.5 partsof demineralized water were added and stirred for 5 minutes at 80° C.Next, 10% of a monomer feed, consisting of 132.9 parts of demineralizedwater, 13.0 parts of a 30 wt-% solution of sodium lauryl sulphate inwater, 23.3 parts of methacrylic acid, 280.1 parts of dibutyl itaconate,and 280.1 parts of methyl methacrylate, was added, after the temperaturerose to approximately 90° C. due to the exothermic nature of thepolymerization. As soon as the temperature of 90° C. was reached, theremaining monomer feed and the initiator feed, consisting of 58.7 partsof demineralized water, 2.5 parts of sodium persulphate, and 3.7 partsof a 30 wt-% solution of sodium lauryl sulphate in water, were started.Both feeds were added over a period of 2 hours. At the end of themonomer feed the feed tank was rinsed with 10.4 parts of demineralizedwater. The temperature of the reactor contents were cooled to 80° C.,after which a solution of 1.8 parts of iso-ascorbic acid dissolved in26.5 parts of demineralized water (which was brought to a pH of 8.5using an ammonia solution) was fed over a period of 30 minutes, duringwhich a mixture of 2.8 parts of t-butyl hydroperoxide and 5.6 parts ofdemineralized water was added in two shots; one at the start of theiso-ascorbic acid feed and 15 minutes later.

At the end of the feed, the mixture was stirred at 80° C. for 30minutes, and the pH was raised to 7.2 using a 25 wt-% solution ofammonia in water. After stirring for another 30 minutes, the batch wascooled to room temperature. The solids content was adjusted to 40% usingdemineralized water.

Comparative Example Comp II BA and MMA Containing Polymer

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer were charged 639.5 parts of demineralized water, 0.5 parts ofsodium bicarbonate, and 13.3 parts of a 30 wt-% solution of sodiumlauryl sulphate in water. The reactor contents were heated to 80° C.,after which a solution of 0.8 parts of sodium persulphate in 4.5 partsof demineralized water were added and stirred for 5 minutes at 80° C.Next, 10% of a monomer feed, consisting of 132.9 parts of demineralizedwater, 13.0 parts of a 30 wt-% solution of sodium lauryl sulphate inwater, 23.3 parts of methacrylic acid, 280.1 parts of butyl acrylate,and 280.1 parts of methyl methacrylate, was added, after the temperaturerose to approximately 90° C. due to the exothermic nature of thepolymerization. As soon as the temperature of 90° C. was reached, theremaining monomer feed and the initiator feed, consisting of 58.7 partsof demineralized water, 2.5 parts of sodium persulphate, and 3.7 partsof a 30 wt-% solution of sodium lauryl sulphate in water, were started.Both feeds were added over a period of 2 hours. At the end of themonomer feed the feed tank was rinsed with 10.4 parts of demineralizedwater. The temperature of the reactor contents were cooled to 80° C.,after which a solution of 1.8 parts of iso-ascorbic acid dissolved in26.5 parts of demineralized water (which was brought to a pH of 8.5using an ammonia solution) was fed over a period of 30 minutes, duringwhich a mixture of 2.8 parts of t-butyl hydroperoxide and 5.6 parts ofdemineralized water was added in two shots; one at the start of theiso-ascorbic acid feed and 15 minutes later.

At the end of the feed, the mixture was stirred at 80° C. for 30minutes, and the pH was raised to 7.2 using a 25 wt-% solution ofammonia in water. After stirring for another 30 minutes, the batch wascooled to room temperature. The solids content was adjusted to 40% usingdemineralized water.

Comparative Example Comp III DMI Containing Copolymer

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer were charged 639.5 parts of demineralized water, 0.5 parts ofsodium bicarbonate, and 13.3 parts of a 30 wt-% solution of sodiumlauryl sulphate in water. The reactor contents were heated to 80° C.,after which a solution of 0.8 parts of sodium persulphate in 4.5 partsof demineralized water were added and stirred for 5 minutes at 80° C.Next, 10% of a monomer feed, consisting of 132.9 parts of demineralizedwater, 13.0 parts of a 30 wt-% solution of sodium lauryl sulphate inwater, 23.3 parts of methacrylic acid, 414.3 parts of dimethylitaconate, and 145.9 parts of ethyl acrylate, was added, after thetemperature rose to approximately 90° C. due to the exothermic nature ofthe polymerization. As soon as the temperature of 90° C. was reached,the remaining monomer feed and the initiator feed, consisting of 58.7parts of demineralized water, 2.5 parts of sodium persulphate, and 3.7parts of a 30 wt-% solution of sodium lauryl sulphate in water, werestarted. Both feeds should be added over a period of 2 hours.

After 110 minutes of the monomer feed, the emulsion gelled, showing thathigher itaconates, such as DBI, yield superior properties over loweritaconates, such as DMI.

TABLE 4 Film properties; “5” means excellent resistance properties, nodamage to the film, “1” indicated completely destroyed film Water spottest Blocking Stain resistance König 1 16 resis- (16 hrs)* hardness hrhrs tance EtOH Andy Coffee (s) Ex 16 5 5 3 5 4 5 201 Comp I 5 4 1 4 2 5110 Ex 17 5 5 5 4 4 5 173 Comp II 5 3 3 3 2 4 115 Comp III Could not beprepared due to instable processing. *Determined as spot test.

In all cases (except Comp III), the water spot was good. Blockingresistance and König hardness were in all cases better for the polymersaccording to the invention compared to their most similar comparativeexamples. While resistance to coffee and ethanol were comparable betweenpolymers according to the invention and the comparatives, the resistanceto soap (Andy) was clearly better for the polymers according to theinvention.

Example 18 MMA/DMI/AA

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer are charged 394.0 parts of 2-butanone. The reactor contents areheated to 80° C. As soon as the polymerization temperature is reached,13.3 parts of azobis(2-methyl butyronitrile) are added and the monomerfeed and catalyst feed are started. The monomer feed consists of 244.4parts of methyl methacrylate, 244.4 parts of dimethyl itaconate, and244.4 parts of acrylic acid. The catalyst feed consists of 31.1 parts ofazobis(2-methyl butyronitrile) dissolved in 125.9 parts of 2-butanone.Both feeds are added over a period of 180 minutes.

At the end of the feeds 2.5 parts of azobis(2-methyl butyronitrile) areadded and the mixture is stirred at 80° C. for another 150 minutes. Themixture is cooled to room temperature.

To 615.8 parts of the polymer solution is added a mixture of 99.6 partsof a 25 wt-% of ammonia in water, and 1080.5 parts of water. Next, the2-butanone is removed at 50° C. under reduced pressure. The solidscontent is corrected to 22.5% using demineralized water and the pH iscorrected to 8.6-8.8 using a 25 wt-% solution of ammonia in water.

The final polymer solution has a solids content of 22.5% and a pH of8.7.

Example 19 S/DMI/AA

To a round-bottomed flask equipped with a condenser, thermometer, and astirrer are charged 394.0 parts of 2-butanone. The reactor contents areheated to 80° C. As soon as the polymerization temperature is reached,13.3 parts of azobis(2-methyl butyronitrile) are added and the monomerfeed and catalyst feed are started. The monomer feed consists of 244.4parts of styrene, 244.4 parts of dimethyl itaconate, and 244.4 parts ofacrylic acid. The catalyst feed consists of 31.1 parts ofazobis(2-methyl butyronitrile) dissolved in 125.9 parts of 2-butanone.Both feeds are added over a period of 180 minutes. At the end of thefeeds 2.5 parts of azobis(2-methyl butyronitrile) are added and themixture is stirred at 80° C. for another 150 minutes. The mixture iscooled to room temperature. To 546.1 parts of polymer solution is addeda mixture of 105.4 parts of a 25 wt-% of ammonia in water, and 1144.1parts of water. Next, the 2-butanone is removed at 50° C. under reducedpressure. The solids content is corrected to 22.5% using demineralizedwater and the pH is corrected to 8.6-8.8 using a 25 wt-% solution ofammonia in water. The final polymer solution has a solids content of22.4% and a pH of 8.6.

Example 20 MMA/DMI/AA

To a high pressure reactor equipped with a thermometer, and a stirrerare charged 500.0 parts of 2-butanone. The reactor contents are heatedto 140° C. As soon as the polymerization temperature is reached, 2.9parts of di-t-butyl peroxide and 40 parts of 2-butanone are added. 5minutes later the monomer feed is started. The monomer feed consists of331.8 parts of methyl methacrylate, 331.8 parts of dimethyl itaconate,331.8 parts of acrylic acid, 5.7 parts of di-t-butyl peroxide, and 6.6parts of t-butyl perbenzoate, and is added over a period of 180 minutesat 140° C. At the end of the feed the feed tank is rinsed with 90.9parts of 2-butanone. 45 minutes after completion of the monomer feed 2.5parts of t-butyl perbenzoate dissolved in 40 parts of 2-butanone areadded and the mixture is stirred at 140° C. for another 45 minutes.Next, 2.5 parts of t-butyl perbenzoate dissolved in 40 parts of2-butanone are added and the mixture is stirred for another 135 minutesat 140° C. The mixture is cooled to room temperature. To 619.3 parts ofthe polymer solution is added a mixture of 99.3 parts of a 25 wt-% ofammonia in water, and 1077.3 parts of water. Next, the 2-butanone isremoved at 50° C. under reduced pressure. The solids content iscorrected to 22.5% using demineralized water and the pH is corrected to8.6-8.8 using a 25 wt-% solution of ammonia in water. The final polymersolution has a solids content of 22.5% and a pH of 8.6.

Example 21 S/DMI/AA

To a high pressure reactor equipped with a thermometer, and a stirrerare charged 500.0 parts of 2-butanone. The reactor contents are heatedto 140° C. As soon as the polymerization temperature is reached, 4.4parts of di-t-butyl peroxide and 40 parts of 2-butanone are added. 5minutes later the monomer feed is started. The monomer feed consists of331.8 parts of styrene, 331.8 parts of dimethyl itaconate, 331.8 partsof acrylic acid, 8.6 parts of di-t-butyl peroxide, and 10.0 parts oft-butyl perbenzoate, and is added over a period of 180 minutes at 140°C. At the end of the feed the feed tank is rinsed with 90.9 parts of2-butanone. 45 minutes after completion of the monomer feed 2.5 parts oft-butyl perbenzoate dissolved in 40 parts of 2-butanone are added andthe mixture is stirred at 140° C. for another 45 minutes. Next, 2.5parts of t-butyl perbenzoate dissolved in 40 parts of 2-butanone areadded and the mixture is stirred for another 135 minutes at 140° C. Themixture is cooled to room temperature. To 617.8 parts of the polymersolution is added a mixture of 99.4 parts of a 25 wt-% of ammonia inwater, and 1078.6 parts of water. Next, the 2-butanone is removed at 50°C. under reduced pressure. The solids content is corrected to 22.5%using demineralized water and the pH is corrected to 8.6-8.8 using a 25wt-% solution of ammonia in water. The final polymer solution has asolids content of 22.5% and a pH of 8.7.

The invention claimed is:
 1. An oligomer-polymer composition comprisingan oligomer composition O having a weight average molecular weight offrom 1000 to 150,000 g/mol (measured by GPC), and a polymer compositionP having a weight average molecular weight of at least 80,000 g/mol(measured by GPC), wherein the oligomer composition O and the polymercomposition P each independently comprise a copolymer comprising: (a)optionally at least 23% by weight of at least one monomer represented byFormula 1:

 where both R₁ and R₂ independently represent an optionally substitutedhydrocarbo moiety having from 4 to 10 carbon atoms, (b) optionally atleast one hydrophilic monomer in an amount sufficient that the resultantcopolymer has an acid value less than 150 mg KOH per g of polymer, (c)optionally of one or more monomers represented by Formula 2:

 where R₃ and R₄ independently represent H or an optionally substitutedhydrocarbo moiety having from 1 to 20 carbon atoms  X₁ and X₂independently represents O or NR₅ where R₅ denotes H or an optionallysubstituted hydrocarbo moiety having from 1 to 20 carbon atoms  with theproviso that when X₁ and/or X₂ are O then the respective R₃ and/or R₄attached to the oxy group independently represent an optionallysubstituted hydrocarbo having from 1 to 3 carbon atoms (d) optionallyless than 77% by weight of monomers other than components (a), (b) or(c), where the percentages or amounts of (a), (b) (c) (d) are by weightcalculated as a proportion of the total weight of (a)+(b)+(c)+(d) andthus total 100%; where independently at least one of the components (a),(b), (c), (d) and the copolymer obtained from components (a), (b), (c)and/or (d) is biorenewable as defined by an amount of carbon-14sufficient to produce a decay of at least about 1.5 disintegrations perminute per gram carbon (dpm/gC); and where at least one component (a) ispresent in either oligomer composition O or polymer composition P, andwherein the oligomer-polymer composition comprises: (a) component (a) inan amount from 24% to 70% by weight being one or more monomersrepresented by Formula 1 (b) component (b) being one or more acidfunctional monomer(s) in an amount from 0.5% to 15% by weight, in anamount also sufficient that the resultant copolymer has an acid value offrom 3 to 100 mg KOH per g of polymer, (c) component (c) in an amountfrom 0.01% to 10% by weight being one or more monomers represented byFormula 2 in which X₁ and X₂ are both O and R₃ and/or R₄ independentlyrepresent an optionally substituted hydrocarbo having from 1 to 3 carbonatoms, (d) component (d) if present in an amount less than 75% by weightof monomer(s) other than components (a), (b) or (c) not containingstyrene, butyl acrylate, 2-ethyl hexyl acrylate and/or mixtures thereof;and with the provisos that where the copolymer is prepared by anemulsion polymerisation a chaser monomer is not used; the copolymer isnot prepared in the presence of a seed polymer comprising apoly(itaconate ester); the copolymer is not prepared in the presence ofan initiator system comprising an organoborane amine complex.
 2. Anoligomer-polymer composition as claimed in claim 1, wherein component(a) comprises dibutyl itaconate.
 3. An oligomer-polymer composition asclaimed in claim 1, wherein at least one of composition O and/or P: (a)component (a) is present in an amount of from 30 to 65 wt-% and isdibutyl itaconate; (b) optional component (b) if present is present inan amount of up to 10 wt-% and comprises an acid functionalethylenically unsaturated monomer and/or anhydride thereof; (c) optionalcomponent (c) if present is present in an amount of from 1 to 25 wt-%and is dimethyl itaconate and/or diethyl itaconate; (d) optionalcomponent (d) if present is present in an amount such that (a) and (d),and (b) and (c) where present, total 100% by weight.
 4. Anoligomer-polymer composition as claimed in claim 1 in which at least onecomponent (d) comprises at least one polymer precursor(s) of Formula 3

wherein, Y denotes an electronegative group, R₆ is H, OH or anoptionally hydroxy substituted C₁₋₁₀hydrcarbo R₇ is H or aC₁₋₁₀hydrocarbo; R₈ is a C₁₋₁₀hydrocarbo group substituted by at leastone activated unsaturated moiety comprising at least one unsaturatedcarbon-to-carbon double bond in chemical proximity to at least oneactivating moiety; and either: A represents a divalent organo moietyattached to both the —HN— and —Y— moieties so the -A-, —NR₆—, —C(═O)—and —Y— moieties together represent a ring of 4 to 8 ring atoms, and R₇and R₈ are attached to any suitable point on the ring; or A is notpresent (and Formula 3 represents a linear and/or branched moiety thatdoes not comprise a heterocyclic ring) in which case R₇ and R₈ areattached to R₆; and m is an integer from 1 to
 4. 5. An aqueous polymerdispersion comprising an oligomer-polymer composition as claimed inclaim 1, wherein the aqueous polymer dispersion exhibits a minimum filmforming temperature below 50° C. and comprises a vinyl copolymer derivedfrom olefinically unsaturated monomers, with at least two phasescomprising: A) 40 to 90 wt-% of a vinyl polymer A having a glasstransition temperature in the range of from −50 to 30 C; and B) 10 to 60wt-% of a vinyl polymer B having a glass transition temperature therange of from 50 to 130° C.; wherein at least one of the monomers usedto prepare the vinyl polymer A and/or the vinyl polymer B isdi(n-butyl)itaconate (DBI) in an amount from 20 to 80 wt-% of the totalmonomers, wherein optionally 10% by weight of the total amount ofmonomer used to form the vinyl polymer A and the vinyl polymer Bcomprises an amount of carbon-14 sufficient to produce a decay of atleast about 1.5 dpm/gC; and wherein the weight percentage of monomers inthe vinyl polymer A and the vinyl polymer B are calculated based on thetotal amount of olefinically unsaturated monomers used to prepare thevinyl polymer A and the vinyl polymer B=100%; and wherein the vinylpolymer A comprises 0.1 to 10 wt-% of at least one acid-functionalolefinically unsaturated monomer, where the weight percentage of acidfunctional monomer is calculated based on the total amount ofolefinically unsaturated monomer used to prepare polymer A=100%.
 6. Aprocess for preparing a copolymer as claimed in claim 1, the processcomprising the step of polymerising polymer precursors in apolymerisation method the polymer precursors comprising component (a),component (b) and optionally components (c) and/or component (d),wherein optionally the polymerisation method is selected from aqueousemulsion polymerisation and suspension polymerisation and where themethod does not comprise a chaser monomer step.
 7. A coating compositioncomprising an oligomer-polymer composition as claimed in claim
 1. 8. Asubstrate and/or article having coated thereon an optionally curedcoating composition of claim
 7. 9. A method for preparing a coatedsubstrate and/or article comprising the steps of applying a coatingcomposition of claim 7 to the substrate and/or article and optionallycuring said composition in situ to form a cured coating thereon.
 10. Anaqueous vinyl polymer coating composition comprising an oligomer-polymercomposition as claimed in claim 1, wherein the composition comprises: a)a vinyl polymer C (optionally corresponding to oligomer composition O),comprising: α[alpha])(i) 1 to 45 wt-% of acid-functional olefinicallyunsaturated monomers; α[alpha])(ii) 0 to 25 wt-% ofcrosslinking-functional olefinically unsaturated monomers; andα[alpha])(iii) 99 to 50 wt-% of non-acid functional, non-crosslinkingolefinically unsaturated and/or stryenically unsaturated monomers;wherein the weight percentages of each of (α[alpha])(i), (α[alpha])(ii)and (α[alpha])(iii) are calculated based on the total of(α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii) being 100%; and wherein thevinyl polymer C has a molecular weight within the range of from 1,000 to150,000 g/mol and an acid value>5 mgKOH/g; and b) a vinyl polymer D(optionally corresponding to polymer composition P), comprising:β[beta](i) 0 to 10 wt-% of acid-functional olefinically unsaturatedmonomers; β[beta](ii) 0 to 25 wt-% of crosslinking-functionalolefinically unsaturated monomers; and β[beta](iii) 0 to 90 wt-% ofnon-acid functional, non-crosslinking monomers selected from the groupconsisting of olefinically unsaturated monomers and arylarylalkylenemonomers other than those of Formula 1; at least one ofβ[beta](i), β[beta](ii) and β[beta](iii) being present; wherein theweight percentages of each of ((β[beta](i), (β[beta])(ii),(β[beta])(iii) and (β[beta])(iv) are calculated based on the total of(β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)=100%; andwherein the vinyl polymer D has a molecular weight of at least 80,000g/mol and an acid value less than 65 mgKOH/g, wherein I) the weight % ofolefinically unsaturated monomers and aryl arylalkylene monomers used toform the vinyl polymer C and the vinyl polymer D when calculated basedon the total amount of(α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii)+(β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)=100%are in the respective weight percentages of from 5 to 75% for the vinylpolymer C, and from 25% to 95% for vinyl polymer D, II) from 20 to 75wt-%, by weight of the total amount of monomers(α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii)+(β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)used to form the vinyl polymer C and the vinyl polymer D comprises atleast one monomer of Formula 1; III) optionally at least 10%, preferablyat least 20% by weight of the total amount of monomers (α[alpha])(i)+(α[alpha])(ii)+(α[alpha])(iii)+(β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv)used to form the vinyl polymer C and the vinyl polymer D is derived fromat least one bio-renewable olefinically unsaturated monomer; IV) theacid value of the vinyl polymer C is greater than the acid value ofpolymer B by at least 10 mgKOH; V) the vinyl polymer C and the vinylpolymer D have a glass transition temperature difference of at least 20°C.; VI) the vinyl polymer D is prepared in the presence of the vinylpolymer C; and VII) the coating composition has a minimum film formingtemperature of <55° C. and on drying has a Koenig hardness of at least20 sec.
 11. An aqueous vinyl polymer coating composition as claimed inclaim 10, wherein from 24 to 60 wt-%, by weight of the total amount ofmonomers (α[alpha]) (i)+(α[alpha]) (ii)+(α[alpha])(iii)+(β[beta])(i)+(β[beta])(ii)+(β[beta])(iii)+(β[beta])(iv) used toform the vinyl polymer C and the vinyl polymer D comprises at least onemonomer of Formula
 1. 12. A method for preparing a coating compositionwhich comprises combining the oligomer-polymer composition according toclaim 1 with a solvent.